hbase/conf/hbase-default.xml

<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
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<configuration>
  <property>
    <name>hbase.rootdir</name>
    <value>file:///tmp/hbase-${user.name}/hbase</value>
    <description>The directory shared by region servers.
    Should be fully-qualified to include the filesystem to use.
    E.g: hdfs://NAMENODE_SERVER:PORT/HBASE_ROOTDIR
    </description>
  </property>
  <property>
    <name>hbase.master.port</name>
    <value>60000</value>
    <description>The port master should bind to.</description>
  </property>
  <property>
    <name>hbase.cluster.distributed</name>
    <value>false</value>
    <description>The mode the cluster will be in. Possible values are
      false: standalone and pseudo-distributed setups with managed Zookeeper
      true: fully-distributed with unmanaged Zookeeper Quorum (see hbase-env.sh)
    </description>
  </property>
  <property>
    <name>hbase.tmp.dir</name>
    <value>/tmp/hbase-${user.name}</value>
    <description>Temporary directory on the local filesystem.</description>
  </property>
  <property>
    <name>hbase.master.info.port</name>
    <value>60010</value>
    <description>The port for the hbase master web UI
    Set to -1 if you do not want the info server to run.
    </description>
  </property>
  <property>
    <name>hbase.master.info.bindAddress</name>
    <value>0.0.0.0</value>
    <description>The address for the hbase master web UI
    </description>
  </property>
  <property>
    <name>hbase.client.write.buffer</name>
    <value>2097152</value>
    <description>Size of the 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 reduces the number of RPC.  
    For an estimate of server-side memory-used, evaluate
    hbase.client.write.buffer * hbase.regionserver.handler.count
    </description>
  </property>
  <property>
    <name>hbase.master.meta.thread.rescanfrequency</name>
    <value>60000</value>
    <description>How long the HMaster sleeps (in milliseconds) between scans of
    the root and meta tables.
    </description>
  </property>
  <property>
    <name>hbase.master.lease.period</name>
    <value>120000</value>
    <description>HMaster server lease period in milliseconds. Default is
    120 seconds.  Region servers must report in within this period else
    they are considered dead.  On loaded cluster, may need to up this
    period.</description>
  </property>
  <property>
    <name>hbase.regionserver.port</name>
    <value>60020</value>
    <description>The port an HBase region server binds to.
    </description>
  </property>
  <property>
    <name>hbase.regionserver.info.port</name>
    <value>60030</value>
    <description>The port for the hbase regionserver web UI
    Set to -1 if you do not want the info server to run.
    </description>
  </property>
  <property>
    <name>hbase.regionserver.info.port.auto</name>
    <value>false</value>
    <description>Info server auto port bind. Enables automatic port
    search if hbase.regionserver.info.port is already in use.
    Useful for testing, turned off by default.
    </description>
  </property>
  <property>
    <name>hbase.regionserver.info.bindAddress</name>
    <value>0.0.0.0</value>
    <description>The address for the hbase regionserver web UI
    </description>
  </property>
  <property>
    <name>hbase.regionserver.class</name>
    <value>org.apache.hadoop.hbase.ipc.HRegionInterface</value>
    <description>An interface that is assignable to HRegionInterface.  Used in HClient for
    opening proxy to remote region server.
    </description>
  </property>
  <property>
    <name>hbase.client.pause</name>
    <value>2000</value>
    <description>General client pause value.  Used mostly as value to wait
    before running a retry of a failed get, region lookup, etc.</description>
  </property>
  <property>
    <name>hbase.client.retries.number</name>
    <value>10</value>
    <description>Maximum retries.  Used as maximum for all retryable
    operations such as fetching of the root region from root region
    server, getting a cell's value, starting a row update, etc.
    Default: 10.
    </description>
  </property>
  <property>
    <name>hbase.client.scanner.caching</name>
    <value>1</value>
    <description>Number of rows that will be fetched when calling next
    on a scanner if it is not served from 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.
    </description>
  </property>
  <property>
    <name>hbase.regionserver.lease.period</name>
    <value>60000</value>
    <description>HRegion server lease period in milliseconds. Default is
    60 seconds. Clients must report in within this period else they are
    considered dead.</description>
  </property>
  <property>
    <name>hbase.regionserver.handler.count</name>
    <value>10</value>
    <description>Count of RPC Server instances spun up on RegionServers
    Same property is used by the HMaster for count of master handlers.
    Default is 10.
    </description>
  </property>
  <property>
    <name>hbase.regionserver.msginterval</name>
    <value>3000</value>
    <description>Interval between messages from the RegionServer to HMaster
    in milliseconds.  Default is 3 seconds.
    </description>
  </property>
  <property>
    <name>hbase.regionserver.flushlogentries</name>
    <value>100</value>
    <description>Sync the HLog to the HDFS when it has accumulated this many
    entries. Default 100. Value is checked on every HLog.append
    </description>
  </property>
  <property>
    <name>hbase.regionserver.optionallogflushinterval</name>
    <value>10000</value>
    <description>Sync the HLog to the HDFS after this interval if it has not
    accumulated enough entries to trigger a sync. Default 10 seconds. Units:
    milliseconds.
    </description>
  </property>
  <property>
    <name>hbase.regionserver.logroll.period</name>
    <value>3600000</value>
    <description>Period at which we will roll the commit log.</description>
  </property>
  <property>
    <name>hbase.regionserver.thread.splitcompactcheckfrequency</name>
    <value>20000</value>
    <description>How often a region server runs the split/compaction check.
    </description>
  </property>
  <property>
    <name>hbase.regionserver.nbreservationblocks</name>
    <value>4</value>
    <description>The number of reservation blocks which are used to prevent
    unstable region servers caused by an OOME.
    </description>
  </property>
  <property>
    <name>hbase.zookeeper.dns.interface</name>
    <value>default</value>
    <description>The name of the Network Interface from which a ZooKeeper server
      should report its IP address.
    </description>
  </property>
  <property>
    <name>hbase.zookeeper.dns.nameserver</name>
    <value>default</value>
    <description>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.
    </description>
  </property>
  <property>
    <name>hbase.regionserver.dns.interface</name>
    <value>default</value>
    <description>The name of the Network Interface from which a region server 
      should report its IP address.
    </description>
  </property>
  <property>
    <name>hbase.regionserver.dns.nameserver</name>
    <value>default</value>
    <description>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.
    </description>
  </property>
  <property>
    <name>hbase.master.dns.interface</name>
    <value>default</value>
    <description>The name of the Network Interface from which a master 
      should report its IP address.
    </description>
  </property>
  <property>
    <name>hbase.master.dns.nameserver</name>
    <value>default</value>
    <description>The host name or IP address of the name server (DNS)
      which a master should use to determine the host name used 
      for communication and display purposes.
    </description>
  </property>
  <property>
    <name>hbase.regionserver.global.memstore.upperLimit</name>
    <value>0.4</value>
    <description>Maximum size of all memstores in a region server before new 
      updates are blocked and flushes are forced. Defaults to 40% of heap
    </description>
  </property>
  <property>
    <name>hbase.regionserver.global.memstore.lowerLimit</name>
    <value>0.25</value>
    <description>When memstores are being forced to flush to make room in
      memory, keep flushing until we hit this mark. Defaults to 30% of heap. 
      This value equal to hbase.regionserver.global.memstore.upperLimit causes
      the minimum possible flushing to occur when updates are blocked due to 
      memstore limiting.
    </description>
  </property>  
  <property>
    <name>hbase.hbasemaster.maxregionopen</name>
    <value>120000</value>
    <description>Period to wait for a region open.  If regionserver
    takes longer than this interval, assign to a new regionserver.
    </description>
  </property>
  <property>
    <name>hbase.regions.percheckin</name>
    <value>10</value>
    <description>Maximum number of regions that can be assigned in a single go
    to a region server.
    </description>
  </property>
  <property>
    <name>hbase.server.thread.wakefrequency</name>
    <value>10000</value>
    <description>Time to sleep in between searches for work (in milliseconds).
    Used as sleep interval by service threads such as META scanner and log roller.
    </description>
  </property>
  <property>
    <name>hbase.hregion.memstore.flush.size</name>
    <value>67108864</value>
    <description>
    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.
    </description>
  </property>
  <property>
    <name>hbase.hregion.memstore.block.multiplier</name>
    <value>2</value>
    <description>
    Block updates if memstore has hbase.hregion.block.memstore
    time hbase.hregion.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.
    </description>
  </property>
  <property>
    <name>hbase.hregion.max.filesize</name>
    <value>268435456</value>
    <description>
    Maximum HStoreFile size. If any one of a column families' HStoreFiles has
    grown to exceed this value, the hosting HRegion is split in two.
    Default: 256M.
    </description>
  </property>
  <property>
    <name>hbase.hstore.compactionThreshold</name>
    <value>3</value>
    <description>
    If more than this number of HStoreFiles in any one HStore
    (one HStoreFile is written per flush of memstore) then a compaction
    is run to rewrite all HStoreFiles files as one.  Larger numbers
    put off compaction but when it runs, it takes longer to complete.
    During a compaction, updates cannot be flushed to disk.  Long
    compactions require memory sufficient to carry the logging of
    all updates across the duration of the compaction.
    
    If too large, clients timeout during compaction.
    </description>
  </property>
  <property>
    <name>hbase.hstore.compaction.max</name>
    <value>10</value>
    <description>Max number of HStoreFiles to compact per 'minor' compaction.
    </description>
  </property>
  <property>
    <name>hbase.hregion.majorcompaction</name>
    <value>86400000</value>
    <description>The time (in miliseconds) between 'major' compactions of all
    HStoreFiles in a region.  Default: 1 day.
    </description>
  </property>
  <property>
    <name>hbase.regions.slop</name>
    <value>0.1</value>
    <description>Rebalance if regionserver has average + (average * slop) regions.
    Default is 10% slop.
    </description>
  </property>
  <property>
    <name>hfile.min.blocksize.size</name>
    <value>65536</value>
    <description>Minimum store file block size.  The smaller you make this, the
    bigger your index and the less you fetch on a random-access.  Set size down
    if you have small cells and want faster random-access of individual cells.
    </description>
  </property>
  <property>
      <name>hfile.block.cache.size</name>
      <value>0.2</value>
      <description>
          Percentage of maximum heap (-Xmx setting) to allocate to block cache
          used by HFile/StoreFile. Default of 0.2 means allocate 20%.
          Set to 0 to disable.
      </description>
  </property>
  <property>
    <name>hbase.hstore.blockCache.blockSize</name>
    <value>16384</value>
    <description>The size of each block in the block cache.
    Enable blockcaching on a per column family basis; see the BLOCKCACHE setting
    in HColumnDescriptor.  Blocks are kept in a java Soft Reference cache so are
    let go when high pressure on memory.  Block caching is not enabled by default.
    </description>
  </property>
  <property>
    <name>hbase.hash.type</name>
    <value>murmur</value>
    <description>The hashing algorithm for use in HashFunction. Two values are
    supported now: murmur (MurmurHash) and jenkins (JenkinsHash).
    </description>
  </property>
  <property>
    <name>zookeeper.session.timeout</name>
    <value>30000</value>
    <description>ZooKeeper session timeout. This option is not used by HBase
      directly, it is for the internals of ZooKeeper. HBase merely passes it in
      whenever a connection is established to ZooKeeper. It is used by ZooKeeper
      for hearbeats. In milliseconds.
    </description>
  </property>
  <property>
    <name>zookeeper.retries</name>
    <value>5</value>
    <description>How many times to retry connections to ZooKeeper. Used for
      reading/writing root region location, checking/writing out of safe mode.
      Used together with ${zookeeper.pause} in an exponential backoff fashion
      when making queries to ZooKeeper.
    </description>
  </property>
  <property>
    <name>zookeeper.pause</name>
    <value>2000</value>
    <description>Sleep time between retries to ZooKeeper. In milliseconds. Used
      together with ${zookeeper.retries} in an exponential backoff fashion when
      making queries to ZooKeeper.
    </description>
  </property>
  <property>
    <name>zookeeper.znode.parent</name>
    <value>/hbase</value>
    <description>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.
    </description>
  </property>
  <property>
    <name>zookeeper.znode.rootserver</name>
    <value>root-region-server</value>
    <description>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.
    </description>
  </property>
  <property>
    <name>zookeeper.znode.safemode</name>
    <value>safe-mode</value>
    <description>Path to ephemeral ZNode signifying cluster is out of safe mode.
      This is created by the master when scanning is done. Clients wait for this
      node before querying the cluster. If a relative path is given, the parent
      folder will be ${zookeeper.znode.parent}. By default, this means the safe
      mode flag is stored at /hbase/safe-mode.
    </description>
  </property>

  <!--
  The following three properties are used together to create the list of
  host:peer_port:leader_port quorum servers for ZooKeeper.
  -->
  <property>
    <name>hbase.zookeeper.quorum</name>
    <value>localhost</value>
    <description>Comma separated list of servers in the ZooKeeper Quorum.
    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 quorum servers. If HBASE_MANAGES_ZK is set in hbase-env.sh
    this is the list of servers which we will start/stop ZooKeeper on.
    </description>
  </property>
  <property>
    <name>hbase.zookeeper.peerport</name>
    <value>2888</value>
    <description>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.
    </description>
  </property>
  <property>
    <name>hbase.zookeeper.leaderport</name>
    <value>3888</value>
    <description>Port used by ZooKeeper for leader election.
    See http://hadoop.apache.org/zookeeper/docs/r3.1.1/zookeeperStarted.html#sc_RunningReplicatedZooKeeper
    for more information.
    </description>
  </property>
  <!-- End of properties used to generate ZooKeeper host:port quorum list. -->

  <!--
  Beginning of properties that are directly mapped from ZooKeeper's zoo.cfg.
  All properties with an "hbase.zookeeper.property." prefix are converted for
  ZooKeeper's configuration. Hence, if you want to add an option from zoo.cfg,
  e.g.  "initLimit=10" you would append the following to your configuration:
    <property>
      <name>hbase.zookeeper.property.initLimit</name>
      <value>10</value>
    </property>
  -->
  <property>
    <name>hbase.zookeeper.property.tickTime</name>
    <value>2000</value>
    <description>Property from ZooKeeper's config zoo.cfg.
    The number of milliseconds of each tick.
    </description>
  </property>
  <property>
    <name>hbase.zookeeper.property.initLimit</name>
    <value>10</value>
    <description>Property from ZooKeeper's config zoo.cfg.
    The number of ticks that the initial synchronization phase can take.
    </description>
  </property>
  <property>
    <name>hbase.zookeeper.property.syncLimit</name>
    <value>5</value>
    <description>Property from ZooKeeper's config zoo.cfg.
    The number of ticks that can pass between sending a request and getting an
    acknowledgment.
    </description>
  </property>
  <property>
    <name>hbase.zookeeper.property.dataDir</name>
    <value>${hbase.tmp.dir}/zookeeper</value>
    <description>Property from ZooKeeper's config zoo.cfg.
    The directory where the snapshot is stored.
    </description>
  </property>
  <property>
    <name>hbase.zookeeper.property.clientPort</name>
    <value>2181</value>
    <description>Property from ZooKeeper's config zoo.cfg.
    The port at which the clients will connect.
    </description>
  </property>
  <property>
    <name>hbase.zookeeper.property.maxClientCnxns</name>
    <value>30</value>
    <description>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.
    </description>
  </property>
  <!-- End of properties that are directly mapped from ZooKeeper's zoo.cfg -->
</configuration>