HBASE-12738 Addendum to fix up hbase-default.xml mistake

This commit is contained in:
Misty Stanley-Jones 2014-12-23 07:28:48 +10:00
parent 4d53fe5dcd
commit 83db450fc6
2 changed files with 2 additions and 540 deletions

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<xi:include
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<section
xml:id="hbase_default_configurations">
<title />
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</section>
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<?xml version="1.0" encoding="UTF-8"?><glossary xml:id="hbase_default_configurations" version="5.0" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:m="http://www.w3.org/1998/Math/MathML" xmlns:db="http://docbook.org/ns/docbook" xmlns:xi="http://www.w3.org/2001/XInclude" xmlns:svg="http://www.w3.org/2000/svg" xmlns:html="http://www.w3.org/1999/xhtml" xmlns="http://docbook.org/ns/docbook"><title>HBase Default Configuration</title><para>
The documentation below is generated using the default hbase configuration file,
<filename>hbase-default.xml</filename>, as source.
</para><glossentry xml:id="hbase.tmp.dir"><glossterm><varname>hbase.tmp.dir</varname></glossterm><glossdef><para>Temporary directory on the local filesystem.
Change this setting to point to a location more permanent
than '/tmp', the usual resolve for java.io.tmpdir, as the
'/tmp' directory is cleared on machine restart.</para><formalpara><title>Default</title><para><varname>${java.io.tmpdir}/hbase-${user.name}</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.rootdir"><glossterm><varname>hbase.rootdir</varname></glossterm><glossdef><para>The directory shared by region servers and into
which HBase persists. The URL should be 'fully-qualified'
to include the filesystem scheme. For example, to specify the
HDFS directory '/hbase' where the HDFS instance's namenode is
running at namenode.example.org on port 9000, set this value to:
hdfs://namenode.example.org:9000/hbase. By default, we write
to whatever ${hbase.tmp.dir} is set too -- usually /tmp --
so change this configuration or else all data will be lost on
machine restart.</para><formalpara><title>Default</title><para><varname>${hbase.tmp.dir}/hbase</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.cluster.distributed"><glossterm><varname>hbase.cluster.distributed</varname></glossterm><glossdef><para>The mode the cluster will be in. Possible values are
false for standalone mode and true for distributed mode. If
false, startup will run all HBase and ZooKeeper daemons together
in the one JVM.</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.zookeeper.quorum"><glossterm><varname>hbase.zookeeper.quorum</varname></glossterm><glossdef><para>Comma separated list of servers in the ZooKeeper ensemble
(This config. should have been named hbase.zookeeper.ensemble).
For example, "host1.mydomain.com,host2.mydomain.com,host3.mydomain.com".
By default this is set to localhost for local and pseudo-distributed modes
of operation. For a fully-distributed setup, this should be set to a full
list of ZooKeeper ensemble servers. If HBASE_MANAGES_ZK is set in hbase-env.sh
this is the list of servers which hbase will start/stop ZooKeeper on as
part of cluster start/stop. Client-side, we will take this list of
ensemble members and put it together with the hbase.zookeeper.clientPort
config. and pass it into zookeeper constructor as the connectString
parameter.</para><formalpara><title>Default</title><para><varname>localhost</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.local.dir"><glossterm><varname>hbase.local.dir</varname></glossterm><glossdef><para>Directory on the local filesystem to be used
as a local storage.</para><formalpara><title>Default</title><para><varname>${hbase.tmp.dir}/local/</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.master.info.port"><glossterm><varname>hbase.master.info.port</varname></glossterm><glossdef><para>The port for the HBase Master web UI.
Set to -1 if you do not want a UI instance run.</para><formalpara><title>Default</title><para><varname>16010</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.master.info.bindAddress"><glossterm><varname>hbase.master.info.bindAddress</varname></glossterm><glossdef><para>The bind address for the HBase Master web UI
</para><formalpara><title>Default</title><para><varname>0.0.0.0</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.master.logcleaner.plugins"><glossterm><varname>hbase.master.logcleaner.plugins</varname></glossterm><glossdef><para>A comma-separated list of BaseLogCleanerDelegate invoked by
the LogsCleaner service. These WAL cleaners are called in order,
so put the cleaner that prunes the most files in front. To
implement your own BaseLogCleanerDelegate, just put it in HBase's classpath
and add the fully qualified class name here. Always add the above
default log cleaners in the list.</para><formalpara><title>Default</title><para><varname>org.apache.hadoop.hbase.master.cleaner.TimeToLiveLogCleaner</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.master.logcleaner.ttl"><glossterm><varname>hbase.master.logcleaner.ttl</varname></glossterm><glossdef><para>Maximum time a WAL can stay in the .oldlogdir directory,
after which it will be cleaned by a Master thread.</para><formalpara><title>Default</title><para><varname>600000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.master.hfilecleaner.plugins"><glossterm><varname>hbase.master.hfilecleaner.plugins</varname></glossterm><glossdef><para>A comma-separated list of BaseHFileCleanerDelegate invoked by
the HFileCleaner service. These HFiles cleaners are called in order,
so put the cleaner that prunes the most files in front. To
implement your own BaseHFileCleanerDelegate, just put it in HBase's classpath
and add the fully qualified class name here. Always add the above
default log cleaners in the list as they will be overwritten in
hbase-site.xml.</para><formalpara><title>Default</title><para><varname>org.apache.hadoop.hbase.master.cleaner.TimeToLiveHFileCleaner</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.master.catalog.timeout"><glossterm><varname>hbase.master.catalog.timeout</varname></glossterm><glossdef><para>Timeout value for the Catalog Janitor from the master to
META.</para><formalpara><title>Default</title><para><varname>600000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.master.infoserver.redirect"><glossterm><varname>hbase.master.infoserver.redirect</varname></glossterm><glossdef><para>Whether or not the Master listens to the Master web
UI port (hbase.master.info.port) and redirects requests to the web
UI server shared by the Master and RegionServer.</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.port"><glossterm><varname>hbase.regionserver.port</varname></glossterm><glossdef><para>The port the HBase RegionServer binds to.</para><formalpara><title>Default</title><para><varname>16020</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.info.port"><glossterm><varname>hbase.regionserver.info.port</varname></glossterm><glossdef><para>The port for the HBase RegionServer web UI
Set to -1 if you do not want the RegionServer UI to run.</para><formalpara><title>Default</title><para><varname>16030</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.info.bindAddress"><glossterm><varname>hbase.regionserver.info.bindAddress</varname></glossterm><glossdef><para>The address for the HBase RegionServer web UI</para><formalpara><title>Default</title><para><varname>0.0.0.0</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.info.port.auto"><glossterm><varname>hbase.regionserver.info.port.auto</varname></glossterm><glossdef><para>Whether or not the Master or RegionServer
UI should search for a port to bind to. Enables automatic port
search if hbase.regionserver.info.port is already in use.
Useful for testing, turned off by default.</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.handler.count"><glossterm><varname>hbase.regionserver.handler.count</varname></glossterm><glossdef><para>Count of RPC Listener instances spun up on RegionServers.
Same property is used by the Master for count of master handlers.</para><formalpara><title>Default</title><para><varname>30</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.ipc.server.callqueue.handler.factor"><glossterm><varname>hbase.ipc.server.callqueue.handler.factor</varname></glossterm><glossdef><para>Factor to determine the number of call queues.
A value of 0 means a single queue shared between all the handlers.
A value of 1 means that each handler has its own queue.</para><formalpara><title>Default</title><para><varname>0.1</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.ipc.server.callqueue.read.ratio"><glossterm><varname>hbase.ipc.server.callqueue.read.ratio</varname></glossterm><glossdef><para>Split the call queues into read and write queues.
The specified interval (which should be between 0.0 and 1.0)
will be multiplied by the number of call queues.
A value of 0 indicate to not split the call queues, meaning that both read and write
requests will be pushed to the same set of queues.
A value lower than 0.5 means that there will be less read queues than write queues.
A value of 0.5 means there will be the same number of read and write queues.
A value greater than 0.5 means that there will be more read queues than write queues.
A value of 1.0 means that all the queues except one are used to dispatch read requests.
Example: Given the total number of call queues being 10
a read.ratio of 0 means that: the 10 queues will contain both read/write requests.
a read.ratio of 0.3 means that: 3 queues will contain only read requests
and 7 queues will contain only write requests.
a read.ratio of 0.5 means that: 5 queues will contain only read requests
and 5 queues will contain only write requests.
a read.ratio of 0.8 means that: 8 queues will contain only read requests
and 2 queues will contain only write requests.
a read.ratio of 1 means that: 9 queues will contain only read requests
and 1 queues will contain only write requests.
</para><formalpara><title>Default</title><para><varname>0</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.ipc.server.callqueue.scan.ratio"><glossterm><varname>hbase.ipc.server.callqueue.scan.ratio</varname></glossterm><glossdef><para>Given the number of read call queues, calculated from the total number
of call queues multiplied by the callqueue.read.ratio, the scan.ratio property
will split the read call queues into small-read and long-read queues.
A value lower than 0.5 means that there will be less long-read queues than short-read queues.
A value of 0.5 means that there will be the same number of short-read and long-read queues.
A value greater than 0.5 means that there will be more long-read queues than short-read queues
A value of 0 or 1 indicate to use the same set of queues for gets and scans.
Example: Given the total number of read call queues being 8
a scan.ratio of 0 or 1 means that: 8 queues will contain both long and short read requests.
a scan.ratio of 0.3 means that: 2 queues will contain only long-read requests
and 6 queues will contain only short-read requests.
a scan.ratio of 0.5 means that: 4 queues will contain only long-read requests
and 4 queues will contain only short-read requests.
a scan.ratio of 0.8 means that: 6 queues will contain only long-read requests
and 2 queues will contain only short-read requests.
</para><formalpara><title>Default</title><para><varname>0</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.msginterval"><glossterm><varname>hbase.regionserver.msginterval</varname></glossterm><glossdef><para>Interval between messages from the RegionServer to Master
in milliseconds.</para><formalpara><title>Default</title><para><varname>3000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.regionSplitLimit"><glossterm><varname>hbase.regionserver.regionSplitLimit</varname></glossterm><glossdef><para>Limit for the number of regions after which no more region
splitting should take place. This is not a hard limit for the number of
regions but acts as a guideline for the regionserver to stop splitting after
a certain limit. Default is MAX_INT; i.e. do not block splitting.</para><formalpara><title>Default</title><para><varname>2147483647</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.logroll.period"><glossterm><varname>hbase.regionserver.logroll.period</varname></glossterm><glossdef><para>Period at which we will roll the commit log regardless
of how many edits it has.</para><formalpara><title>Default</title><para><varname>3600000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.logroll.errors.tolerated"><glossterm><varname>hbase.regionserver.logroll.errors.tolerated</varname></glossterm><glossdef><para>The number of consecutive WAL close errors we will allow
before triggering a server abort. A setting of 0 will cause the
region server to abort if closing the current WAL writer fails during
log rolling. Even a small value (2 or 3) will allow a region server
to ride over transient HDFS errors.</para><formalpara><title>Default</title><para><varname>2</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.hlog.reader.impl"><glossterm><varname>hbase.regionserver.hlog.reader.impl</varname></glossterm><glossdef><para>The WAL file reader implementation.</para><formalpara><title>Default</title><para><varname>org.apache.hadoop.hbase.regionserver.wal.ProtobufLogReader</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.hlog.writer.impl"><glossterm><varname>hbase.regionserver.hlog.writer.impl</varname></glossterm><glossdef><para>The WAL file writer implementation.</para><formalpara><title>Default</title><para><varname>org.apache.hadoop.hbase.regionserver.wal.ProtobufLogWriter</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.master.distributed.log.replay"><glossterm><varname>hbase.master.distributed.log.replay</varname></glossterm><glossdef><para>Enable 'distributed log replay' as default engine splitting
WAL files on server crash. This default is new in hbase 1.0. To fall
back to the old mode 'distributed log splitter', set the value to
'false'. 'Disributed log replay' improves MTTR because it does not
write intermediate files. 'DLR' required that 'hfile.format.version'
be set to version 3 or higher.
</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.global.memstore.size"><glossterm><varname>hbase.regionserver.global.memstore.size</varname></glossterm><glossdef><para>Maximum size of all memstores in a region server before new
updates are blocked and flushes are forced. Defaults to 40% of heap.
Updates are blocked and flushes are forced until size of all memstores
in a region server hits hbase.regionserver.global.memstore.size.lower.limit.</para><formalpara><title>Default</title><para><varname>0.4</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.global.memstore.size.lower.limit"><glossterm><varname>hbase.regionserver.global.memstore.size.lower.limit</varname></glossterm><glossdef><para>Maximum size of all memstores in a region server before flushes are forced.
Defaults to 95% of hbase.regionserver.global.memstore.size.
A 100% value for this value causes the minimum possible flushing to occur when updates are
blocked due to memstore limiting.</para><formalpara><title>Default</title><para><varname>0.95</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.optionalcacheflushinterval"><glossterm><varname>hbase.regionserver.optionalcacheflushinterval</varname></glossterm><glossdef><para>
Maximum amount of time an edit lives in memory before being automatically flushed.
Default 1 hour. Set it to 0 to disable automatic flushing.</para><formalpara><title>Default</title><para><varname>3600000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.catalog.timeout"><glossterm><varname>hbase.regionserver.catalog.timeout</varname></glossterm><glossdef><para>Timeout value for the Catalog Janitor from the regionserver to META.</para><formalpara><title>Default</title><para><varname>600000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.dns.interface"><glossterm><varname>hbase.regionserver.dns.interface</varname></glossterm><glossdef><para>The name of the Network Interface from which a region server
should report its IP address.</para><formalpara><title>Default</title><para><varname>default</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.dns.nameserver"><glossterm><varname>hbase.regionserver.dns.nameserver</varname></glossterm><glossdef><para>The host name or IP address of the name server (DNS)
which a region server should use to determine the host name used by the
master for communication and display purposes.</para><formalpara><title>Default</title><para><varname>default</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.region.split.policy"><glossterm><varname>hbase.regionserver.region.split.policy</varname></glossterm><glossdef><para>
A split policy determines when a region should be split. The various other split policies that
are available currently are ConstantSizeRegionSplitPolicy, DisabledRegionSplitPolicy,
DelimitedKeyPrefixRegionSplitPolicy, KeyPrefixRegionSplitPolicy etc.
</para><formalpara><title>Default</title><para><varname>org.apache.hadoop.hbase.regionserver.IncreasingToUpperBoundRegionSplitPolicy</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="zookeeper.session.timeout"><glossterm><varname>zookeeper.session.timeout</varname></glossterm><glossdef><para>ZooKeeper session timeout in milliseconds. It is used in two different ways.
First, this value is used in the ZK client that HBase uses to connect to the ensemble.
It is also used by HBase when it starts a ZK server and it is passed as the 'maxSessionTimeout'. See
http://hadoop.apache.org/zookeeper/docs/current/zookeeperProgrammers.html#ch_zkSessions.
For example, if a HBase region server connects to a ZK ensemble that's also managed by HBase, then the
session timeout will be the one specified by this configuration. But, a region server that connects
to an ensemble managed with a different configuration will be subjected that ensemble's maxSessionTimeout. So,
even though HBase might propose using 90 seconds, the ensemble can have a max timeout lower than this and
it will take precedence. The current default that ZK ships with is 40 seconds, which is lower than HBase's.
</para><formalpara><title>Default</title><para><varname>90000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="zookeeper.znode.parent"><glossterm><varname>zookeeper.znode.parent</varname></glossterm><glossdef><para>Root ZNode for HBase in ZooKeeper. All of HBase's ZooKeeper
files that are configured with a relative path will go under this node.
By default, all of HBase's ZooKeeper file path are configured with a
relative path, so they will all go under this directory unless changed.</para><formalpara><title>Default</title><para><varname>/hbase</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="zookeeper.znode.rootserver"><glossterm><varname>zookeeper.znode.rootserver</varname></glossterm><glossdef><para>Path to ZNode holding root region location. This is written by
the master and read by clients and region servers. If a relative path is
given, the parent folder will be ${zookeeper.znode.parent}. By default,
this means the root location is stored at /hbase/root-region-server.</para><formalpara><title>Default</title><para><varname>root-region-server</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="zookeeper.znode.acl.parent"><glossterm><varname>zookeeper.znode.acl.parent</varname></glossterm><glossdef><para>Root ZNode for access control lists.</para><formalpara><title>Default</title><para><varname>acl</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.zookeeper.dns.interface"><glossterm><varname>hbase.zookeeper.dns.interface</varname></glossterm><glossdef><para>The name of the Network Interface from which a ZooKeeper server
should report its IP address.</para><formalpara><title>Default</title><para><varname>default</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.zookeeper.dns.nameserver"><glossterm><varname>hbase.zookeeper.dns.nameserver</varname></glossterm><glossdef><para>The host name or IP address of the name server (DNS)
which a ZooKeeper server should use to determine the host name used by the
master for communication and display purposes.</para><formalpara><title>Default</title><para><varname>default</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.zookeeper.peerport"><glossterm><varname>hbase.zookeeper.peerport</varname></glossterm><glossdef><para>Port used by ZooKeeper peers to talk to each other.
See http://hadoop.apache.org/zookeeper/docs/r3.1.1/zookeeperStarted.html#sc_RunningReplicatedZooKeeper
for more information.</para><formalpara><title>Default</title><para><varname>2888</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.zookeeper.leaderport"><glossterm><varname>hbase.zookeeper.leaderport</varname></glossterm><glossdef><para>Port used by ZooKeeper for leader election.
See http://hadoop.apache.org/zookeeper/docs/r3.1.1/zookeeperStarted.html#sc_RunningReplicatedZooKeeper
for more information.</para><formalpara><title>Default</title><para><varname>3888</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.zookeeper.useMulti"><glossterm><varname>hbase.zookeeper.useMulti</varname></glossterm><glossdef><para>Instructs HBase to make use of ZooKeeper's multi-update functionality.
This allows certain ZooKeeper operations to complete more quickly and prevents some issues
with rare Replication failure scenarios (see the release note of HBASE-2611 for an example).
IMPORTANT: only set this to true if all ZooKeeper servers in the cluster are on version 3.4+
and will not be downgraded. ZooKeeper versions before 3.4 do not support multi-update and
will not fail gracefully if multi-update is invoked (see ZOOKEEPER-1495).</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.config.read.zookeeper.config"><glossterm><varname>hbase.config.read.zookeeper.config</varname></glossterm><glossdef><para>
Set to true to allow HBaseConfiguration to read the
zoo.cfg file for ZooKeeper properties. Switching this to true
is not recommended, since the functionality of reading ZK
properties from a zoo.cfg file has been deprecated.</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.zookeeper.property.initLimit"><glossterm><varname>hbase.zookeeper.property.initLimit</varname></glossterm><glossdef><para>Property from ZooKeeper's config zoo.cfg.
The number of ticks that the initial synchronization phase can take.</para><formalpara><title>Default</title><para><varname>10</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.zookeeper.property.syncLimit"><glossterm><varname>hbase.zookeeper.property.syncLimit</varname></glossterm><glossdef><para>Property from ZooKeeper's config zoo.cfg.
The number of ticks that can pass between sending a request and getting an
acknowledgment.</para><formalpara><title>Default</title><para><varname>5</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.zookeeper.property.dataDir"><glossterm><varname>hbase.zookeeper.property.dataDir</varname></glossterm><glossdef><para>Property from ZooKeeper's config zoo.cfg.
The directory where the snapshot is stored.</para><formalpara><title>Default</title><para><varname>${hbase.tmp.dir}/zookeeper</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.zookeeper.property.clientPort"><glossterm><varname>hbase.zookeeper.property.clientPort</varname></glossterm><glossdef><para>Property from ZooKeeper's config zoo.cfg.
The port at which the clients will connect.</para><formalpara><title>Default</title><para><varname>2181</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.zookeeper.property.maxClientCnxns"><glossterm><varname>hbase.zookeeper.property.maxClientCnxns</varname></glossterm><glossdef><para>Property from ZooKeeper's config zoo.cfg.
Limit on number of concurrent connections (at the socket level) that a
single client, identified by IP address, may make to a single member of
the ZooKeeper ensemble. Set high to avoid zk connection issues running
standalone and pseudo-distributed.</para><formalpara><title>Default</title><para><varname>300</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.client.write.buffer"><glossterm><varname>hbase.client.write.buffer</varname></glossterm><glossdef><para>Default size of the HTable client write buffer in bytes.
A bigger buffer takes more memory -- on both the client and server
side since server instantiates the passed write buffer to process
it -- but a larger buffer size reduces the number of RPCs made.
For an estimate of server-side memory-used, evaluate
hbase.client.write.buffer * hbase.regionserver.handler.count</para><formalpara><title>Default</title><para><varname>2097152</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.client.pause"><glossterm><varname>hbase.client.pause</varname></glossterm><glossdef><para>General client pause value. Used mostly as value to wait
before running a retry of a failed get, region lookup, etc.
See hbase.client.retries.number for description of how we backoff from
this initial pause amount and how this pause works w/ retries.</para><formalpara><title>Default</title><para><varname>100</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.client.retries.number"><glossterm><varname>hbase.client.retries.number</varname></glossterm><glossdef><para>Maximum retries. Used as maximum for all retryable
operations such as the getting of a cell's value, starting a row update,
etc. Retry interval is a rough function based on hbase.client.pause. At
first we retry at this interval but then with backoff, we pretty quickly reach
retrying every ten seconds. See HConstants#RETRY_BACKOFF for how the backup
ramps up. Change this setting and hbase.client.pause to suit your workload.</para><formalpara><title>Default</title><para><varname>35</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.client.max.total.tasks"><glossterm><varname>hbase.client.max.total.tasks</varname></glossterm><glossdef><para>The maximum number of concurrent tasks a single HTable instance will
send to the cluster.</para><formalpara><title>Default</title><para><varname>100</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.client.max.perserver.tasks"><glossterm><varname>hbase.client.max.perserver.tasks</varname></glossterm><glossdef><para>The maximum number of concurrent tasks a single HTable instance will
send to a single region server.</para><formalpara><title>Default</title><para><varname>5</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.client.max.perregion.tasks"><glossterm><varname>hbase.client.max.perregion.tasks</varname></glossterm><glossdef><para>The maximum number of concurrent connections the client will
maintain to a single Region. That is, if there is already
hbase.client.max.perregion.tasks writes in progress for this region, new puts
won't be sent to this region until some writes finishes.</para><formalpara><title>Default</title><para><varname>1</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.client.scanner.caching"><glossterm><varname>hbase.client.scanner.caching</varname></glossterm><glossdef><para>Number of rows that will be fetched when calling next
on a scanner if it is not served from (local, client) memory. Higher
caching values will enable faster scanners but will eat up more memory
and some calls of next may take longer and longer times when the cache is empty.
Do not set this value such that the time between invocations is greater
than the scanner timeout; i.e. hbase.client.scanner.timeout.period</para><formalpara><title>Default</title><para><varname>100</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.client.keyvalue.maxsize"><glossterm><varname>hbase.client.keyvalue.maxsize</varname></glossterm><glossdef><para>Specifies the combined maximum allowed size of a KeyValue
instance. This is to set an upper boundary for a single entry saved in a
storage file. Since they cannot be split it helps avoiding that a region
cannot be split any further because the data is too large. It seems wise
to set this to a fraction of the maximum region size. Setting it to zero
or less disables the check.</para><formalpara><title>Default</title><para><varname>10485760</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.client.scanner.timeout.period"><glossterm><varname>hbase.client.scanner.timeout.period</varname></glossterm><glossdef><para>Client scanner lease period in milliseconds.</para><formalpara><title>Default</title><para><varname>60000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.client.localityCheck.threadPoolSize"><glossterm><varname>hbase.client.localityCheck.threadPoolSize</varname></glossterm><glossdef><para/><formalpara><title>Default</title><para><varname>2</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.bulkload.retries.number"><glossterm><varname>hbase.bulkload.retries.number</varname></glossterm><glossdef><para>Maximum retries. This is maximum number of iterations
to atomic bulk loads are attempted in the face of splitting operations
0 means never give up.</para><formalpara><title>Default</title><para><varname>10</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.balancer.period&#10; "><glossterm><varname>hbase.balancer.period
</varname></glossterm><glossdef><para>Period at which the region balancer runs in the Master.</para><formalpara><title>Default</title><para><varname>300000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regions.slop"><glossterm><varname>hbase.regions.slop</varname></glossterm><glossdef><para>Rebalance if any regionserver has average + (average * slop) regions.</para><formalpara><title>Default</title><para><varname>0.2</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.server.thread.wakefrequency"><glossterm><varname>hbase.server.thread.wakefrequency</varname></glossterm><glossdef><para>Time to sleep in between searches for work (in milliseconds).
Used as sleep interval by service threads such as log roller.</para><formalpara><title>Default</title><para><varname>10000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.server.versionfile.writeattempts"><glossterm><varname>hbase.server.versionfile.writeattempts</varname></glossterm><glossdef><para>
How many time to retry attempting to write a version file
before just aborting. Each attempt is seperated by the
hbase.server.thread.wakefrequency milliseconds.</para><formalpara><title>Default</title><para><varname>3</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hregion.memstore.flush.size"><glossterm><varname>hbase.hregion.memstore.flush.size</varname></glossterm><glossdef><para>
Memstore will be flushed to disk if size of the memstore
exceeds this number of bytes. Value is checked by a thread that runs
every hbase.server.thread.wakefrequency.</para><formalpara><title>Default</title><para><varname>134217728</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hregion.percolumnfamilyflush.size.lower.bound"><glossterm><varname>hbase.hregion.percolumnfamilyflush.size.lower.bound</varname></glossterm><glossdef><para>
If FlushLargeStoresPolicy is used, then every time that we hit the
total memstore limit, we find out all the column families whose memstores
exceed this value, and only flush them, while retaining the others whose
memstores are lower than this limit. If none of the families have their
memstore size more than this, all the memstores will be flushed
(just as usual). This value should be less than half of the total memstore
threshold (hbase.hregion.memstore.flush.size).
</para><formalpara><title>Default</title><para><varname>16777216</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hregion.preclose.flush.size"><glossterm><varname>hbase.hregion.preclose.flush.size</varname></glossterm><glossdef><para>
If the memstores in a region are this size or larger when we go
to close, run a "pre-flush" to clear out memstores before we put up
the region closed flag and take the region offline. On close,
a flush is run under the close flag to empty memory. During
this time the region is offline and we are not taking on any writes.
If the memstore content is large, this flush could take a long time to
complete. The preflush is meant to clean out the bulk of the memstore
before putting up the close flag and taking the region offline so the
flush that runs under the close flag has little to do.</para><formalpara><title>Default</title><para><varname>5242880</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hregion.memstore.block.multiplier"><glossterm><varname>hbase.hregion.memstore.block.multiplier</varname></glossterm><glossdef><para>
Block updates if memstore has hbase.hregion.memstore.block.multiplier
times hbase.hregion.memstore.flush.size bytes. Useful preventing
runaway memstore during spikes in update traffic. Without an
upper-bound, memstore fills such that when it flushes the
resultant flush files take a long time to compact or split, or
worse, we OOME.</para><formalpara><title>Default</title><para><varname>4</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hregion.memstore.mslab.enabled"><glossterm><varname>hbase.hregion.memstore.mslab.enabled</varname></glossterm><glossdef><para>
Enables the MemStore-Local Allocation Buffer,
a feature which works to prevent heap fragmentation under
heavy write loads. This can reduce the frequency of stop-the-world
GC pauses on large heaps.</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hregion.max.filesize"><glossterm><varname>hbase.hregion.max.filesize</varname></glossterm><glossdef><para>
Maximum HFile size. If the sum of the sizes of a region's HFiles has grown to exceed this
value, the region is split in two.</para><formalpara><title>Default</title><para><varname>10737418240</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hregion.majorcompaction"><glossterm><varname>hbase.hregion.majorcompaction</varname></glossterm><glossdef><para>Time between major compactions, expressed in milliseconds. Set to 0 to disable
time-based automatic major compactions. User-requested and size-based major compactions will
still run. This value is multiplied by hbase.hregion.majorcompaction.jitter to cause
compaction to start at a somewhat-random time during a given window of time. The default value
is 7 days, expressed in milliseconds. If major compactions are causing disruption in your
environment, you can configure them to run at off-peak times for your deployment, or disable
time-based major compactions by setting this parameter to 0, and run major compactions in a
cron job or by another external mechanism.</para><formalpara><title>Default</title><para><varname>604800000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hregion.majorcompaction.jitter"><glossterm><varname>hbase.hregion.majorcompaction.jitter</varname></glossterm><glossdef><para>A multiplier applied to hbase.hregion.majorcompaction to cause compaction to occur
a given amount of time either side of hbase.hregion.majorcompaction. The smaller the number,
the closer the compactions will happen to the hbase.hregion.majorcompaction
interval.</para><formalpara><title>Default</title><para><varname>0.50</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.compactionThreshold"><glossterm><varname>hbase.hstore.compactionThreshold</varname></glossterm><glossdef><para> If more than this number of StoreFiles exist in any one Store
(one StoreFile is written per flush of MemStore), a compaction is run to rewrite all
StoreFiles into a single StoreFile. Larger values delay compaction, but when compaction does
occur, it takes longer to complete.</para><formalpara><title>Default</title><para><varname>3</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.flusher.count"><glossterm><varname>hbase.hstore.flusher.count</varname></glossterm><glossdef><para> The number of flush threads. With fewer threads, the MemStore flushes will be
queued. With more threads, the flushes will be executed in parallel, increasing the load on
HDFS, and potentially causing more compactions. </para><formalpara><title>Default</title><para><varname>2</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.blockingStoreFiles"><glossterm><varname>hbase.hstore.blockingStoreFiles</varname></glossterm><glossdef><para> If more than this number of StoreFiles exist in any one Store (one StoreFile
is written per flush of MemStore), updates are blocked for this region until a compaction is
completed, or until hbase.hstore.blockingWaitTime has been exceeded.</para><formalpara><title>Default</title><para><varname>10</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.blockingWaitTime"><glossterm><varname>hbase.hstore.blockingWaitTime</varname></glossterm><glossdef><para> The time for which a region will block updates after reaching the StoreFile limit
defined by hbase.hstore.blockingStoreFiles. After this time has elapsed, the region will stop
blocking updates even if a compaction has not been completed.</para><formalpara><title>Default</title><para><varname>90000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.compaction.min"><glossterm><varname>hbase.hstore.compaction.min</varname></glossterm><glossdef><para>The minimum number of StoreFiles which must be eligible for compaction before
compaction can run. The goal of tuning hbase.hstore.compaction.min is to avoid ending up with
too many tiny StoreFiles to compact. Setting this value to 2 would cause a minor compaction
each time you have two StoreFiles in a Store, and this is probably not appropriate. If you
set this value too high, all the other values will need to be adjusted accordingly. For most
cases, the default value is appropriate. In previous versions of HBase, the parameter
hbase.hstore.compaction.min was named hbase.hstore.compactionThreshold.</para><formalpara><title>Default</title><para><varname>3</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.compaction.max"><glossterm><varname>hbase.hstore.compaction.max</varname></glossterm><glossdef><para>The maximum number of StoreFiles which will be selected for a single minor
compaction, regardless of the number of eligible StoreFiles. Effectively, the value of
hbase.hstore.compaction.max controls the length of time it takes a single compaction to
complete. Setting it larger means that more StoreFiles are included in a compaction. For most
cases, the default value is appropriate.</para><formalpara><title>Default</title><para><varname>10</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.compaction.min.size"><glossterm><varname>hbase.hstore.compaction.min.size</varname></glossterm><glossdef><para>A StoreFile smaller than this size will always be eligible for minor compaction.
HFiles this size or larger are evaluated by hbase.hstore.compaction.ratio to determine if
they are eligible. Because this limit represents the "automatic include"limit for all
StoreFiles smaller than this value, this value may need to be reduced in write-heavy
environments where many StoreFiles in the 1-2 MB range are being flushed, because every
StoreFile will be targeted for compaction and the resulting StoreFiles may still be under the
minimum size and require further compaction. If this parameter is lowered, the ratio check is
triggered more quickly. This addressed some issues seen in earlier versions of HBase but
changing this parameter is no longer necessary in most situations. Default: 128 MB expressed
in bytes.</para><formalpara><title>Default</title><para><varname>134217728</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.compaction.max.size"><glossterm><varname>hbase.hstore.compaction.max.size</varname></glossterm><glossdef><para>A StoreFile larger than this size will be excluded from compaction. The effect of
raising hbase.hstore.compaction.max.size is fewer, larger StoreFiles that do not get
compacted often. If you feel that compaction is happening too often without much benefit, you
can try raising this value. Default: the value of LONG.MAX_VALUE, expressed in bytes.</para><formalpara><title>Default</title><para><varname>9223372036854775807</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.compaction.ratio"><glossterm><varname>hbase.hstore.compaction.ratio</varname></glossterm><glossdef><para>For minor compaction, this ratio is used to determine whether a given StoreFile
which is larger than hbase.hstore.compaction.min.size is eligible for compaction. Its
effect is to limit compaction of large StoreFiles. The value of hbase.hstore.compaction.ratio
is expressed as a floating-point decimal. A large ratio, such as 10, will produce a single
giant StoreFile. Conversely, a low value, such as .25, will produce behavior similar to the
BigTable compaction algorithm, producing four StoreFiles. A moderate value of between 1.0 and
1.4 is recommended. When tuning this value, you are balancing write costs with read costs.
Raising the value (to something like 1.4) will have more write costs, because you will
compact larger StoreFiles. However, during reads, HBase will need to seek through fewer
StoreFiles to accomplish the read. Consider this approach if you cannot take advantage of
Bloom filters. Otherwise, you can lower this value to something like 1.0 to reduce the
background cost of writes, and use Bloom filters to control the number of StoreFiles touched
during reads. For most cases, the default value is appropriate.</para><formalpara><title>Default</title><para><varname>1.2F</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.compaction.ratio.offpeak"><glossterm><varname>hbase.hstore.compaction.ratio.offpeak</varname></glossterm><glossdef><para>Allows you to set a different (by default, more aggressive) ratio for determining
whether larger StoreFiles are included in compactions during off-peak hours. Works in the
same way as hbase.hstore.compaction.ratio. Only applies if hbase.offpeak.start.hour and
hbase.offpeak.end.hour are also enabled.</para><formalpara><title>Default</title><para><varname>5.0F</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.time.to.purge.deletes"><glossterm><varname>hbase.hstore.time.to.purge.deletes</varname></glossterm><glossdef><para>The amount of time to delay purging of delete markers with future timestamps. If
unset, or set to 0, all delete markers, including those with future timestamps, are purged
during the next major compaction. Otherwise, a delete marker is kept until the major compaction
which occurs after the marker's timestamp plus the value of this setting, in milliseconds.
</para><formalpara><title>Default</title><para><varname>0</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.offpeak.start.hour"><glossterm><varname>hbase.offpeak.start.hour</varname></glossterm><glossdef><para>The start of off-peak hours, expressed as an integer between 0 and 23, inclusive.
Set to -1 to disable off-peak.</para><formalpara><title>Default</title><para><varname>-1</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.offpeak.end.hour"><glossterm><varname>hbase.offpeak.end.hour</varname></glossterm><glossdef><para>The end of off-peak hours, expressed as an integer between 0 and 23, inclusive. Set
to -1 to disable off-peak.</para><formalpara><title>Default</title><para><varname>-1</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.thread.compaction.throttle"><glossterm><varname>hbase.regionserver.thread.compaction.throttle</varname></glossterm><glossdef><para>There are two different thread pools for compactions, one for large compactions and
the other for small compactions. This helps to keep compaction of lean tables (such as
hbase:meta) fast. If a compaction is larger than this threshold, it
goes into the large compaction pool. In most cases, the default value is appropriate. Default:
2 x hbase.hstore.compaction.max x hbase.hregion.memstore.flush.size (which defaults to 128MB).
The value field assumes that the value of hbase.hregion.memstore.flush.size is unchanged from
the default.</para><formalpara><title>Default</title><para><varname>2684354560</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.compaction.kv.max"><glossterm><varname>hbase.hstore.compaction.kv.max</varname></glossterm><glossdef><para>The maximum number of KeyValues to read and then write in a batch when flushing or
compacting. Set this lower if you have big KeyValues and problems with Out Of Memory
Exceptions Set this higher if you have wide, small rows. </para><formalpara><title>Default</title><para><varname>10</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.storescanner.parallel.seek.enable"><glossterm><varname>hbase.storescanner.parallel.seek.enable</varname></glossterm><glossdef><para>
Enables StoreFileScanner parallel-seeking in StoreScanner,
a feature which can reduce response latency under special conditions.</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.storescanner.parallel.seek.threads"><glossterm><varname>hbase.storescanner.parallel.seek.threads</varname></glossterm><glossdef><para>
The default thread pool size if parallel-seeking feature enabled.</para><formalpara><title>Default</title><para><varname>10</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hfile.block.cache.size"><glossterm><varname>hfile.block.cache.size</varname></glossterm><glossdef><para>Percentage of maximum heap (-Xmx setting) to allocate to block cache
used by a StoreFile. Default of 0.4 means allocate 40%.
Set to 0 to disable but it's not recommended; you need at least
enough cache to hold the storefile indices.</para><formalpara><title>Default</title><para><varname>0.4</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hfile.block.index.cacheonwrite"><glossterm><varname>hfile.block.index.cacheonwrite</varname></glossterm><glossdef><para>This allows to put non-root multi-level index blocks into the block
cache at the time the index is being written.</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hfile.index.block.max.size"><glossterm><varname>hfile.index.block.max.size</varname></glossterm><glossdef><para>When the size of a leaf-level, intermediate-level, or root-level
index block in a multi-level block index grows to this size, the
block is written out and a new block is started.</para><formalpara><title>Default</title><para><varname>131072</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.bucketcache.ioengine"><glossterm><varname>hbase.bucketcache.ioengine</varname></glossterm><glossdef><para>Where to store the contents of the bucketcache. One of: onheap,
offheap, or file. If a file, set it to file:PATH_TO_FILE. See https://hbase.apache.org/apidocs/org/apache/hadoop/hbase/io/hfile/CacheConfig.html for more information.
</para><formalpara><title>Default</title><para><varname/></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.bucketcache.combinedcache.enabled"><glossterm><varname>hbase.bucketcache.combinedcache.enabled</varname></glossterm><glossdef><para>Whether or not the bucketcache is used in league with the LRU
on-heap block cache. In this mode, indices and blooms are kept in the LRU
blockcache and the data blocks are kept in the bucketcache.</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.bucketcache.size"><glossterm><varname>hbase.bucketcache.size</varname></glossterm><glossdef><para>The size of the buckets for the bucketcache if you only use a single size.
Defaults to the default blocksize, which is 64 * 1024.</para><formalpara><title>Default</title><para><varname>65536</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.bucketcache.sizes"><glossterm><varname>hbase.bucketcache.sizes</varname></glossterm><glossdef><para>A comma-separated list of sizes for buckets for the bucketcache
if you use multiple sizes. Should be a list of block sizes in order from smallest
to largest. The sizes you use will depend on your data access patterns.</para><formalpara><title>Default</title><para><varname/></para></formalpara></glossdef></glossentry><glossentry xml:id="hfile.format.version"><glossterm><varname>hfile.format.version</varname></glossterm><glossdef><para>The HFile format version to use for new files.
Version 3 adds support for tags in hfiles (See http://hbase.apache.org/book.html#hbase.tags).
Distributed Log Replay requires that tags are enabled. Also see the configuration
'hbase.replication.rpc.codec'.
</para><formalpara><title>Default</title><para><varname>3</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hfile.block.bloom.cacheonwrite"><glossterm><varname>hfile.block.bloom.cacheonwrite</varname></glossterm><glossdef><para>Enables cache-on-write for inline blocks of a compound Bloom filter.</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="io.storefile.bloom.block.size"><glossterm><varname>io.storefile.bloom.block.size</varname></glossterm><glossdef><para>The size in bytes of a single block ("chunk") of a compound Bloom
filter. This size is approximate, because Bloom blocks can only be
inserted at data block boundaries, and the number of keys per data
block varies.</para><formalpara><title>Default</title><para><varname>131072</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.rs.cacheblocksonwrite"><glossterm><varname>hbase.rs.cacheblocksonwrite</varname></glossterm><glossdef><para>Whether an HFile block should be added to the block cache when the
block is finished.</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.rpc.timeout"><glossterm><varname>hbase.rpc.timeout</varname></glossterm><glossdef><para>This is for the RPC layer to define how long HBase client applications
take for a remote call to time out. It uses pings to check connections
but will eventually throw a TimeoutException.</para><formalpara><title>Default</title><para><varname>60000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.rpc.shortoperation.timeout"><glossterm><varname>hbase.rpc.shortoperation.timeout</varname></glossterm><glossdef><para>This is another version of "hbase.rpc.timeout". For those RPC operation
within cluster, we rely on this configuration to set a short timeout limitation
for short operation. For example, short rpc timeout for region server's trying
to report to active master can benefit quicker master failover process.</para><formalpara><title>Default</title><para><varname>10000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.ipc.client.tcpnodelay"><glossterm><varname>hbase.ipc.client.tcpnodelay</varname></glossterm><glossdef><para>Set no delay on rpc socket connections. See
http://docs.oracle.com/javase/1.5.0/docs/api/java/net/Socket.html#getTcpNoDelay()</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.master.keytab.file"><glossterm><varname>hbase.master.keytab.file</varname></glossterm><glossdef><para>Full path to the kerberos keytab file to use for logging in
the configured HMaster server principal.</para><formalpara><title>Default</title><para><varname/></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.master.kerberos.principal"><glossterm><varname>hbase.master.kerberos.principal</varname></glossterm><glossdef><para>Ex. "hbase/_HOST@EXAMPLE.COM". The kerberos principal name
that should be used to run the HMaster process. The principal name should
be in the form: user/hostname@DOMAIN. If "_HOST" is used as the hostname
portion, it will be replaced with the actual hostname of the running
instance.</para><formalpara><title>Default</title><para><varname/></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.keytab.file"><glossterm><varname>hbase.regionserver.keytab.file</varname></glossterm><glossdef><para>Full path to the kerberos keytab file to use for logging in
the configured HRegionServer server principal.</para><formalpara><title>Default</title><para><varname/></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.kerberos.principal"><glossterm><varname>hbase.regionserver.kerberos.principal</varname></glossterm><glossdef><para>Ex. "hbase/_HOST@EXAMPLE.COM". The kerberos principal name
that should be used to run the HRegionServer process. The principal name
should be in the form: user/hostname@DOMAIN. If "_HOST" is used as the
hostname portion, it will be replaced with the actual hostname of the
running instance. An entry for this principal must exist in the file
specified in hbase.regionserver.keytab.file</para><formalpara><title>Default</title><para><varname/></para></formalpara></glossdef></glossentry><glossentry xml:id="hadoop.policy.file"><glossterm><varname>hadoop.policy.file</varname></glossterm><glossdef><para>The policy configuration file used by RPC servers to make
authorization decisions on client requests. Only used when HBase
security is enabled.</para><formalpara><title>Default</title><para><varname>hbase-policy.xml</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.superuser"><glossterm><varname>hbase.superuser</varname></glossterm><glossdef><para>List of users or groups (comma-separated), who are allowed
full privileges, regardless of stored ACLs, across the cluster.
Only used when HBase security is enabled.</para><formalpara><title>Default</title><para><varname/></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.auth.key.update.interval"><glossterm><varname>hbase.auth.key.update.interval</varname></glossterm><glossdef><para>The update interval for master key for authentication tokens
in servers in milliseconds. Only used when HBase security is enabled.</para><formalpara><title>Default</title><para><varname>86400000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.auth.token.max.lifetime"><glossterm><varname>hbase.auth.token.max.lifetime</varname></glossterm><glossdef><para>The maximum lifetime in milliseconds after which an
authentication token expires. Only used when HBase security is enabled.</para><formalpara><title>Default</title><para><varname>604800000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.ipc.client.fallback-to-simple-auth-allowed"><glossterm><varname>hbase.ipc.client.fallback-to-simple-auth-allowed</varname></glossterm><glossdef><para>When a client is configured to attempt a secure connection, but attempts to
connect to an insecure server, that server may instruct the client to
switch to SASL SIMPLE (unsecure) authentication. This setting controls
whether or not the client will accept this instruction from the server.
When false (the default), the client will not allow the fallback to SIMPLE
authentication, and will abort the connection.</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.display.keys"><glossterm><varname>hbase.display.keys</varname></glossterm><glossdef><para>When this is set to true the webUI and such will display all start/end keys
as part of the table details, region names, etc. When this is set to false,
the keys are hidden.</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.coprocessor.region.classes"><glossterm><varname>hbase.coprocessor.region.classes</varname></glossterm><glossdef><para>A comma-separated list of Coprocessors that are loaded by
default on all tables. For any override coprocessor method, these classes
will be called in order. After implementing your own Coprocessor, just put
it in HBase's classpath and add the fully qualified class name here.
A coprocessor can also be loaded on demand by setting HTableDescriptor.</para><formalpara><title>Default</title><para><varname/></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.rest.port"><glossterm><varname>hbase.rest.port</varname></glossterm><glossdef><para>The port for the HBase REST server.</para><formalpara><title>Default</title><para><varname>8080</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.rest.readonly"><glossterm><varname>hbase.rest.readonly</varname></glossterm><glossdef><para>Defines the mode the REST server will be started in. Possible values are:
false: All HTTP methods are permitted - GET/PUT/POST/DELETE.
true: Only the GET method is permitted.</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.rest.threads.max"><glossterm><varname>hbase.rest.threads.max</varname></glossterm><glossdef><para>The maximum number of threads of the REST server thread pool.
Threads in the pool are reused to process REST requests. This
controls the maximum number of requests processed concurrently.
It may help to control the memory used by the REST server to
avoid OOM issues. If the thread pool is full, incoming requests
will be queued up and wait for some free threads.</para><formalpara><title>Default</title><para><varname>100</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.rest.threads.min"><glossterm><varname>hbase.rest.threads.min</varname></glossterm><glossdef><para>The minimum number of threads of the REST server thread pool.
The thread pool always has at least these number of threads so
the REST server is ready to serve incoming requests.</para><formalpara><title>Default</title><para><varname>2</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.rest.support.proxyuser"><glossterm><varname>hbase.rest.support.proxyuser</varname></glossterm><glossdef><para>Enables running the REST server to support proxy-user mode.</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.defaults.for.version.skip"><glossterm><varname>hbase.defaults.for.version.skip</varname></glossterm><glossdef><para>Set to true to skip the 'hbase.defaults.for.version' check.
Setting this to true can be useful in contexts other than
the other side of a maven generation; i.e. running in an
ide. You'll want to set this boolean to true to avoid
seeing the RuntimException complaint: "hbase-default.xml file
seems to be for and old version of HBase (\${hbase.version}), this
version is X.X.X-SNAPSHOT"</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.coprocessor.master.classes"><glossterm><varname>hbase.coprocessor.master.classes</varname></glossterm><glossdef><para>A comma-separated list of
org.apache.hadoop.hbase.coprocessor.MasterObserver coprocessors that are
loaded by default on the active HMaster process. For any implemented
coprocessor methods, the listed classes will be called in order. After
implementing your own MasterObserver, just put it in HBase's classpath
and add the fully qualified class name here.</para><formalpara><title>Default</title><para><varname/></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.coprocessor.abortonerror"><glossterm><varname>hbase.coprocessor.abortonerror</varname></glossterm><glossdef><para>Set to true to cause the hosting server (master or regionserver)
to abort if a coprocessor fails to load, fails to initialize, or throws an
unexpected Throwable object. Setting this to false will allow the server to
continue execution but the system wide state of the coprocessor in question
will become inconsistent as it will be properly executing in only a subset
of servers, so this is most useful for debugging only.</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.online.schema.update.enable"><glossterm><varname>hbase.online.schema.update.enable</varname></glossterm><glossdef><para>Set true to enable online schema changes.</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.table.lock.enable"><glossterm><varname>hbase.table.lock.enable</varname></glossterm><glossdef><para>Set to true to enable locking the table in zookeeper for schema change operations.
Table locking from master prevents concurrent schema modifications to corrupt table
state.</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.table.max.rowsize"><glossterm><varname>hbase.table.max.rowsize</varname></glossterm><glossdef><para>
Maximum size of single row in bytes (default is 1 Gb) for Get'ting
or Scan'ning without in-row scan flag set. If row size exceeds this limit
RowTooBigException is thrown to client.
</para><formalpara><title>Default</title><para><varname>1073741824</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.thrift.minWorkerThreads"><glossterm><varname>hbase.thrift.minWorkerThreads</varname></glossterm><glossdef><para>The "core size" of the thread pool. New threads are created on every
connection until this many threads are created.</para><formalpara><title>Default</title><para><varname>16</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.thrift.maxWorkerThreads"><glossterm><varname>hbase.thrift.maxWorkerThreads</varname></glossterm><glossdef><para>The maximum size of the thread pool. When the pending request queue
overflows, new threads are created until their number reaches this number.
After that, the server starts dropping connections.</para><formalpara><title>Default</title><para><varname>1000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.thrift.maxQueuedRequests"><glossterm><varname>hbase.thrift.maxQueuedRequests</varname></glossterm><glossdef><para>The maximum number of pending Thrift connections waiting in the queue. If
there are no idle threads in the pool, the server queues requests. Only
when the queue overflows, new threads are added, up to
hbase.thrift.maxQueuedRequests threads.</para><formalpara><title>Default</title><para><varname>1000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.thrift.htablepool.size.max"><glossterm><varname>hbase.thrift.htablepool.size.max</varname></glossterm><glossdef><para>The upper bound for the table pool used in the Thrift gateways server.
Since this is per table name, we assume a single table and so with 1000 default
worker threads max this is set to a matching number. For other workloads this number
can be adjusted as needed.
</para><formalpara><title>Default</title><para><varname>1000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.thrift.framed"><glossterm><varname>hbase.regionserver.thrift.framed</varname></glossterm><glossdef><para>Use Thrift TFramedTransport on the server side.
This is the recommended transport for thrift servers and requires a similar setting
on the client side. Changing this to false will select the default transport,
vulnerable to DoS when malformed requests are issued due to THRIFT-601.
</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.thrift.framed.max_frame_size_in_mb"><glossterm><varname>hbase.regionserver.thrift.framed.max_frame_size_in_mb</varname></glossterm><glossdef><para>Default frame size when using framed transport</para><formalpara><title>Default</title><para><varname>2</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.thrift.compact"><glossterm><varname>hbase.regionserver.thrift.compact</varname></glossterm><glossdef><para>Use Thrift TCompactProtocol binary serialization protocol.</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.data.umask.enable"><glossterm><varname>hbase.data.umask.enable</varname></glossterm><glossdef><para>Enable, if true, that file permissions should be assigned
to the files written by the regionserver</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.data.umask"><glossterm><varname>hbase.data.umask</varname></glossterm><glossdef><para>File permissions that should be used to write data
files when hbase.data.umask.enable is true</para><formalpara><title>Default</title><para><varname>000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.metrics.showTableName"><glossterm><varname>hbase.metrics.showTableName</varname></glossterm><glossdef><para>Whether to include the prefix "tbl.tablename" in per-column family metrics.
If true, for each metric M, per-cf metrics will be reported for tbl.T.cf.CF.M, if false,
per-cf metrics will be aggregated by column-family across tables, and reported for cf.CF.M.
In both cases, the aggregated metric M across tables and cfs will be reported.</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.metrics.exposeOperationTimes"><glossterm><varname>hbase.metrics.exposeOperationTimes</varname></glossterm><glossdef><para>Whether to report metrics about time taken performing an
operation on the region server. Get, Put, Delete, Increment, and Append can all
have their times exposed through Hadoop metrics per CF and per region.</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.snapshot.enabled"><glossterm><varname>hbase.snapshot.enabled</varname></glossterm><glossdef><para>Set to true to allow snapshots to be taken / restored / cloned.</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.snapshot.restore.take.failsafe.snapshot"><glossterm><varname>hbase.snapshot.restore.take.failsafe.snapshot</varname></glossterm><glossdef><para>Set to true to take a snapshot before the restore operation.
The snapshot taken will be used in case of failure, to restore the previous state.
At the end of the restore operation this snapshot will be deleted</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.snapshot.restore.failsafe.name"><glossterm><varname>hbase.snapshot.restore.failsafe.name</varname></glossterm><glossdef><para>Name of the failsafe snapshot taken by the restore operation.
You can use the {snapshot.name}, {table.name} and {restore.timestamp} variables
to create a name based on what you are restoring.</para><formalpara><title>Default</title><para><varname>hbase-failsafe-{snapshot.name}-{restore.timestamp}</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.server.compactchecker.interval.multiplier"><glossterm><varname>hbase.server.compactchecker.interval.multiplier</varname></glossterm><glossdef><para>The number that determines how often we scan to see if compaction is necessary.
Normally, compactions are done after some events (such as memstore flush), but if
region didn't receive a lot of writes for some time, or due to different compaction
policies, it may be necessary to check it periodically. The interval between checks is
hbase.server.compactchecker.interval.multiplier multiplied by
hbase.server.thread.wakefrequency.</para><formalpara><title>Default</title><para><varname>1000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.lease.recovery.timeout"><glossterm><varname>hbase.lease.recovery.timeout</varname></glossterm><glossdef><para>How long we wait on dfs lease recovery in total before giving up.</para><formalpara><title>Default</title><para><varname>900000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.lease.recovery.dfs.timeout"><glossterm><varname>hbase.lease.recovery.dfs.timeout</varname></glossterm><glossdef><para>How long between dfs recover lease invocations. Should be larger than the sum of
the time it takes for the namenode to issue a block recovery command as part of
datanode; dfs.heartbeat.interval and the time it takes for the primary
datanode, performing block recovery to timeout on a dead datanode; usually
dfs.client.socket-timeout. See the end of HBASE-8389 for more.</para><formalpara><title>Default</title><para><varname>64000</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.column.max.version"><glossterm><varname>hbase.column.max.version</varname></glossterm><glossdef><para>New column family descriptors will use this value as the default number of versions
to keep.</para><formalpara><title>Default</title><para><varname>1</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.dfs.client.read.shortcircuit.buffer.size"><glossterm><varname>hbase.dfs.client.read.shortcircuit.buffer.size</varname></glossterm><glossdef><para>If the DFSClient configuration
dfs.client.read.shortcircuit.buffer.size is unset, we will
use what is configured here as the short circuit read default
direct byte buffer size. DFSClient native default is 1MB; HBase
keeps its HDFS files open so number of file blocks * 1MB soon
starts to add up and threaten OOME because of a shortage of
direct memory. So, we set it down from the default. Make
it &gt; the default hbase block size set in the HColumnDescriptor
which is usually 64k.
</para><formalpara><title>Default</title><para><varname>131072</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.checksum.verify"><glossterm><varname>hbase.regionserver.checksum.verify</varname></glossterm><glossdef><para>
If set to true (the default), HBase verifies the checksums for hfile
blocks. HBase writes checksums inline with the data when it writes out
hfiles. HDFS (as of this writing) writes checksums to a separate file
than the data file necessitating extra seeks. Setting this flag saves
some on i/o. Checksum verification by HDFS will be internally disabled
on hfile streams when this flag is set. If the hbase-checksum verification
fails, we will switch back to using HDFS checksums (so do not disable HDFS
checksums! And besides this feature applies to hfiles only, not to WALs).
If this parameter is set to false, then hbase will not verify any checksums,
instead it will depend on checksum verification being done in the HDFS client.
</para><formalpara><title>Default</title><para><varname>true</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.bytes.per.checksum"><glossterm><varname>hbase.hstore.bytes.per.checksum</varname></glossterm><glossdef><para>
Number of bytes in a newly created checksum chunk for HBase-level
checksums in hfile blocks.
</para><formalpara><title>Default</title><para><varname>16384</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.hstore.checksum.algorithm"><glossterm><varname>hbase.hstore.checksum.algorithm</varname></glossterm><glossdef><para>
Name of an algorithm that is used to compute checksums. Possible values
are NULL, CRC32, CRC32C.
</para><formalpara><title>Default</title><para><varname>CRC32</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.status.published"><glossterm><varname>hbase.status.published</varname></glossterm><glossdef><para>
This setting activates the publication by the master of the status of the region server.
When a region server dies and its recovery starts, the master will push this information
to the client application, to let them cut the connection immediately instead of waiting
for a timeout.
</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.status.publisher.class"><glossterm><varname>hbase.status.publisher.class</varname></glossterm><glossdef><para>
Implementation of the status publication with a multicast message.
</para><formalpara><title>Default</title><para><varname>org.apache.hadoop.hbase.master.ClusterStatusPublisher$MulticastPublisher</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.status.listener.class"><glossterm><varname>hbase.status.listener.class</varname></glossterm><glossdef><para>
Implementation of the status listener with a multicast message.
</para><formalpara><title>Default</title><para><varname>org.apache.hadoop.hbase.client.ClusterStatusListener$MulticastListener</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.status.multicast.address.ip"><glossterm><varname>hbase.status.multicast.address.ip</varname></glossterm><glossdef><para>
Multicast address to use for the status publication by multicast.
</para><formalpara><title>Default</title><para><varname>226.1.1.3</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.status.multicast.address.port"><glossterm><varname>hbase.status.multicast.address.port</varname></glossterm><glossdef><para>
Multicast port to use for the status publication by multicast.
</para><formalpara><title>Default</title><para><varname>16100</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.dynamic.jars.dir"><glossterm><varname>hbase.dynamic.jars.dir</varname></glossterm><glossdef><para>
The directory from which the custom filter/co-processor jars can be loaded
dynamically by the region server without the need to restart. However,
an already loaded filter/co-processor class would not be un-loaded. See
HBASE-1936 for more details.
</para><formalpara><title>Default</title><para><varname>${hbase.rootdir}/lib</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.security.authentication"><glossterm><varname>hbase.security.authentication</varname></glossterm><glossdef><para>
Controls whether or not secure authentication is enabled for HBase.
Possible values are 'simple' (no authentication), and 'kerberos'.
</para><formalpara><title>Default</title><para><varname>simple</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.rest.filter.classes"><glossterm><varname>hbase.rest.filter.classes</varname></glossterm><glossdef><para>
Servlet filters for REST service.
</para><formalpara><title>Default</title><para><varname>org.apache.hadoop.hbase.rest.filter.GzipFilter</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.master.loadbalancer.class"><glossterm><varname>hbase.master.loadbalancer.class</varname></glossterm><glossdef><para>
Class used to execute the regions balancing when the period occurs.
See the class comment for more on how it works
http://hbase.apache.org/devapidocs/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.html
It replaces the DefaultLoadBalancer as the default (since renamed
as the SimpleLoadBalancer).
</para><formalpara><title>Default</title><para><varname>org.apache.hadoop.hbase.master.balancer.StochasticLoadBalancer</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.security.exec.permission.checks"><glossterm><varname>hbase.security.exec.permission.checks</varname></glossterm><glossdef><para>
If this setting is enabled and ACL based access control is active (the
AccessController coprocessor is installed either as a system coprocessor
or on a table as a table coprocessor) then you must grant all relevant
users EXEC privilege if they require the ability to execute coprocessor
endpoint calls. EXEC privilege, like any other permission, can be
granted globally to a user, or to a user on a per table or per namespace
basis. For more information on coprocessor endpoints, see the coprocessor
section of the HBase online manual. For more information on granting or
revoking permissions using the AccessController, see the security
section of the HBase online manual.
</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.procedure.regionserver.classes"><glossterm><varname>hbase.procedure.regionserver.classes</varname></glossterm><glossdef><para>A comma-separated list of
org.apache.hadoop.hbase.procedure.RegionServerProcedureManager procedure managers that are
loaded by default on the active HRegionServer process. The lifecycle methods (init/start/stop)
will be called by the active HRegionServer process to perform the specific globally barriered
procedure. After implementing your own RegionServerProcedureManager, just put it in
HBase's classpath and add the fully qualified class name here.
</para><formalpara><title>Default</title><para><varname/></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.procedure.master.classes"><glossterm><varname>hbase.procedure.master.classes</varname></glossterm><glossdef><para>A comma-separated list of
org.apache.hadoop.hbase.procedure.MasterProcedureManager procedure managers that are
loaded by default on the active HMaster process. A procedure is identified by its signature and
users can use the signature and an instant name to trigger an execution of a globally barriered
procedure. After implementing your own MasterProcedureManager, just put it in HBase's classpath
and add the fully qualified class name here.</para><formalpara><title>Default</title><para><varname/></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.coordinated.state.manager.class"><glossterm><varname>hbase.coordinated.state.manager.class</varname></glossterm><glossdef><para>Fully qualified name of class implementing coordinated state manager.</para><formalpara><title>Default</title><para><varname>org.apache.hadoop.hbase.coordination.ZkCoordinatedStateManager</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.regionserver.storefile.refresh.period"><glossterm><varname>hbase.regionserver.storefile.refresh.period</varname></glossterm><glossdef><para>
The period (in milliseconds) for refreshing the store files for the secondary regions. 0
means this feature is disabled. Secondary regions sees new files (from flushes and
compactions) from primary once the secondary region refreshes the list of files in the
region (there is no notification mechanism). But too frequent refreshes might cause
extra Namenode pressure. If the files cannot be refreshed for longer than HFile TTL
(hbase.master.hfilecleaner.ttl) the requests are rejected. Configuring HFile TTL to a larger
value is also recommended with this setting.
</para><formalpara><title>Default</title><para><varname>0</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.region.replica.replication.enabled"><glossterm><varname>hbase.region.replica.replication.enabled</varname></glossterm><glossdef><para>
Whether asynchronous WAL replication to the secondary region replicas is enabled or not.
If this is enabled, a replication peer named "region_replica_replication" will be created
which will tail the logs and replicate the mutatations to region replicas for tables that
have region replication &gt; 1. If this is enabled once, disabling this replication also
requires disabling the replication peer using shell or ReplicationAdmin java class.
Replication to secondary region replicas works over standard inter-cluster replication.
So replication, if disabled explicitly, also has to be enabled by setting "hbase.replication"
to true for this feature to work.
</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.http.filter.initializers"><glossterm><varname>hbase.http.filter.initializers</varname></glossterm><glossdef><para>
A comma separated list of class names. Each class in the list must extend
org.apache.hadoop.hbase.http.FilterInitializer. The corresponding Filter will
be initialized. Then, the Filter will be applied to all user facing jsp
and servlet web pages.
The ordering of the list defines the ordering of the filters.
The default StaticUserWebFilter add a user principal as defined by the
hbase.http.staticuser.user property.
</para><formalpara><title>Default</title><para><varname>org.apache.hadoop.hbase.http.lib.StaticUserWebFilter</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.security.visibility.mutations.checkauths"><glossterm><varname>hbase.security.visibility.mutations.checkauths</varname></glossterm><glossdef><para>
This property if enabled, will check whether the labels in the visibility expression are associated
with the user issuing the mutation
</para><formalpara><title>Default</title><para><varname>false</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.http.max.threads"><glossterm><varname>hbase.http.max.threads</varname></glossterm><glossdef><para>
The maximum number of threads that the HTTP Server will create in its
ThreadPool.
</para><formalpara><title>Default</title><para><varname>10</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.replication.rpc.codec"><glossterm><varname>hbase.replication.rpc.codec</varname></glossterm><glossdef><para>
The codec that is to be used when replication is enabled so that
the tags are also replicated. This is used along with HFileV3 which
supports tags in them. If tags are not used or if the hfile version used
is HFileV2 then KeyValueCodec can be used as the replication codec. Note that
using KeyValueCodecWithTags for replication when there are no tags causes no harm.
</para><formalpara><title>Default</title><para><varname>org.apache.hadoop.hbase.codec.KeyValueCodecWithTags</varname></para></formalpara></glossdef></glossentry><glossentry xml:id="hbase.http.staticuser.user"><glossterm><varname>hbase.http.staticuser.user</varname></glossterm><glossdef><para>
The user name to filter as, on static web filters
while rendering content. An example use is the HDFS
web UI (user to be used for browsing files).
</para><formalpara><title>Default</title><para><varname>dr.stack</varname></para></formalpara></glossdef></glossentry></glossary>