Introduce minimal thread scheduler as a base class for `ThreadPool`. Such a class can be used from the `BulkProcessor` to schedule retries and the flush task. This allows to remove the `ThreadPool` dependency from `BulkProcessor`, which requires to provide settings that contain `node.name` and also needed log4j for logging. Instead, it needs now a `Scheduler` that is much lighter and gets automatically created and shut down on close.
Closes#26028
Right now we are attempting to set SO_LINGER to 0 on server channels
when we are stopping the tcp transport. This is not a supported socket
option and throws an exception. This also prevents the channels from
being closed.
This commit 1. doesn't set SO_LINGER for server channges, 2. checks
that it is a supported option in nio, and 3. changes the log message
to warn for server channel close exceptions.
While opening a connection to a node, a channel can subsequently
close. If this happens, a future callback whose purpose is to close all
other channels and disconnect from the node will fire. However, this
future will not be ready to close all the channels because the
connection will not be exposed to the future callback yet. Since this
callback is run once, we will never try to disconnect from this node
again and we will be left with a closed channel. This commit adds a
check that all channels are open before exposing the channel and throws
a general connection exception. In this case, the usual connection retry
logic will take over.
Relates #26932
Today we return a `String[]` that requires copying values for every
access. Yet, we already store the setting as a list so we can also directly
return the unmodifiable list directly. This makes list / array access in settings
a much cheaper operation especially if lists are large.
The shard preference _primary, _replica and its variants were useful
for the asynchronous replication. However, with the current impl, they
are no longer useful and should be removed.
Closes#26335
* Add additional low-level logging handler
We have the trace handler which is useful for recording sent messages
but there are times where it would be useful to have more low-level
logging about the events occurring on a channel. This commit adds a
logging handler that can be enabled by setting a certain log level
(org.elasticsearch.transport.netty4.ESLoggingHandler) to trace that
provides trace logging on low-level channel events and includes some
information about the request/response read/write events on the channel
as well.
* Remove imports
* License header
* Remove redundant
* Add test
* More assertions
Today we represent each value of a list setting with it's own dedicated key
that ends with the index of the value in the list. Aside of the obvious
weirdness this has several issues especially if lists are massive since it
causes massive runtime penalties when validating settings. Like a list of 100k
words will literally cause a create index call to timeout and in-turn massive
slowdown on all subsequent validations runs.
With this change we use a simple string list to represent the list. This change
also forbids to add a settings that ends with a .0 which was internally used to
detect a list setting. Once this has been rolled out for an entire major
version all the internal .0 handling can be removed since all settings will be
converted.
Relates to #26723
Since `#getAsMap` exposes internal representation we are trying to remove it
step by step. This commit is cleaning up some xcontent writing as well as
usage in tests
This commit fixes a #26855. Right now we set SO_LINGER to 0 if we are
stopping the transport. This can throw a ChannelClosedException if the
raw channel is already closed. We have a number of scenarios where it is
possible this could be called with a channel that is already closed.
This commit fixes the issue be checking that the channel is not closed
before attempting to set the socket option.
Currently we only log generic messages about errors in logs from the
nio event handler. This means that we do not know which channel had
issues connection, reading, writing, etc.
This commit changes the logs to include the local and remote addresses
and profile for a channel.
We use group settings historically instead of using a prefix setting which is more restrictive and type safe. The majority of the usecases needs to access a key, value map based on the _leave node_ of the setting ie. the setting `index.tag.*` might be used to tag an index with `index.tag.test=42` and `index.tag.staging=12` which then would be turned into a `{"test": 42, "staging": 12}` map. The group settings would always use `Settings#getAsMap` which is loosing type information and uses internal representation of the settings. Using prefix settings allows now to access such a method type-safe and natively.
Currently we only log generic messages about errors in logs from the
nio event handler. This means that we do not know which channel had
issues connection, reading, writing, etc.
This commit changes the logs to include the local and remote addresses
and profile for a channel.
This change adds a fromXContent method to Settings that allows to read
the xcontent that is produced by toXContent. It also replaces the entire settings
loader infrastructure and removes the structured map representation. Future PRs will
also tackle the `getAsMap` that exposes the internal represenation of settings for
better encapsulation.
It is the exciting return of the global checkpoint background
sync. Long, long ago, in snapshot version far, far away we had and only
had a global checkpoint background sync. This sync would fire
periodically and send the global checkpoint from the primary shard to
the replicas so that they could update their local knowledge of the
global checkpoint. Later in time, as we sped ahead towards finalizing
the initial version of sequence IDs, we realized that we need the global
checkpoint updates to be inline. This means that on a replication
operation, the primary shard would piggy back the global checkpoint with
the replication operation to the replicas. The replicas would update
their local knowledge of the global checkpoint and reply with their
local checkpoint. However, this could allow the global checkpoint on the
primary to advance again and the replicas would fall behind in their
local knowledge of the global checkpoint. If another replication
operation never fired, then the replicas would be permanently behind. To
account for this, we added one more sync that would fire when the
primary shard fell idle. However, this has problems:
- the shard idle timer defaults to five minutes, a long time to wait
for the replicas to learn of the new global checkpoint
- if a replica missed the sync, there was no follow-up sync to catch
them up
- there is an inherent race condition where the primary shard could
fall idle mid-operation (after having sent the replication request to
the replicas); in this case, there would never be a background sync
after the operation completes
- tying the global checkpoint sync to the idle timer was never natural
To fix this, we add two additional changes for the global checkpoint to
be synced to the replicas. The first is that we add a post-operation
sync that only fires if there are no operations in flight and there is a
lagging replica. This gives us a chance to sync the global checkpoint to
the replicas immediately after an operation so that they are always kept
up to date. The second is that we add back a global checkpoint
background sync that fires on a timer. This timer fires every thirty
seconds, and is not configurable (for simplicity). This background sync
is smarter than what we had previously in the sense that it only sends a
sync if the global checkpoint on at least one replica is lagging that of
the primary. When the timer fires, we can compare the global checkpoint
on the primary to its knowledge of the global checkpoint on the replicas
and only send a sync if there is a shard behind.
Relates #26591
Add checks for special permissions before reading hdfs stream data. Also adds test from
readonly repository fix. MiniHDFS will now start with an existing repository with a single snapshot
contained within. Readonly Repository is created in tests and attempts to list the snapshots
within this repo.
Removing several occurrences of this typo in the docs and javadocs, seems to be
a common mistake. Corrections turn up once in a while in PRs, better to correct
some of this in one sweep.
Today we have all non-plugin mappers in core. I'd like to start moving those
that neither map to json datatypes nor are very frequently used like `date` or
`ip` to a module.
This commit creates a new module called `mappers-extra` and moves the
`scaled_float` and `token_count` mappers to it. I'd like to eventually move
`range` fields there but it's more complicated due to their intimate
relationship with range queries.
Relates #10368
Today we don't have a pluggable way to validate if the cluster state
is compatible with the node that joins. We already apply some checks for index
compatibility that prevents nodes to join a cluster with indices it doesn't support
but for plugins this isn't possible. This change adds a cluster state validator that
allows plugins to prevent a join if the cluster-state is incompatible.
This test case was leftover from the static bwc tests. There was still
one use for checking we do not load old indices, but this PR moves the
legacy code needed for that directly into the test. I also opened a
follow up issue to completely remove the unsupported test: #26583.
When determining if a build is a snapshot build, we look for a field in
the JAR manifest. However, when running tests, we are not running with a
compiled core Elasticsearch JAR, we are running with the compiled core
classes on the classpath. We have a fallback for this, we always assume
such a situation is a snapshot build. However, when running builds with
-Dbuild.snapshot=false, this is not the case. As such, we need to
fallback to the value of build.snapshot. However, there are cases where
we are not running with a compiled core Elasticsearch JAR (e.g., when
the transport client is embedded in a web container) so we should only
do this fallback if we are in tests. To verify we are in tests, we check
if randomized runner is on the classpath.
Relates #26554
The percolator will add a `_percolator_document_slot` field to all percolator
hits to indicate with what document it has matched. This number matches with
the order in which the documents have been specified in the percolate query.
Also improved the support for multiple percolate queries in a search request.
We currently have a weird relationship between Transport,
TransportService, and TransportServiceAdaptor. At some point I think
that we would like to collapse these all into one concept as we only
support TCP transports.
This commit moves in that direction by eliminating the adaptor and just
passing the transport service to the transport.
The current script service has a script compilation limit for a one
minute window. This is set to a small default value of 15. Instead of
increasing that default value, this commit introduces a new setting
that allows to configure a rate per time unit, so that the script service can deal with bursts better.
The new setting is named `script.max_compilations_rate`,
requires a nonnegative number and a positive time value.
The default is `75/5m`, which is equivalent to the existing 15 per minute.
* Implement adaptive replica selection
This implements the selection algorithm described in the C3 paper for
determining which copy of the data a query should be routed to.
By using the service time EWMA, response time EWMA, and queue size EWMA we
calculate the score of a node by piggybacking these metrics with each search
request.
Since Elasticsearch lacks the "broadcast to every copy" behavior that Cassandra
has (as mentioned in the C3 paper) to update metrics after a node has been
highly weighted, this implementation adjusts a node's response stats using the
average of the its own and the "best" node's metrics. This is so that a long GC
or other activity that may cause a node's rank to increase dramatically does not
permanently keep a node from having requests routed to it, instead it will
eventually lower its score back to the realm where it is a potential candidate
for new queries.
This feature is off by default and can be turned on with the dynamic setting
`cluster.routing.use_adaptive_replica_selection`.
Relates to #24915, however instead of `b=3` I used `b=4` (after benchmarking)
* Randomly use adaptive replica selection for internal test cluster
* Use an action name *prefix* for retrieving pending requests
* Add unit test for replica selection
* don't use adaptive replica selection in SearchPreferenceIT
* Track client connections in a SearchTransportService instead of TransportService
* Bind `entry` pieces in local variables
* Add javadoc link to C3 paper and javadocs for stat adjustments
* Bind entry's key and value to local variables
* Remove unneeded actionNamePrefix parameter
* Use conns.longValue() instead of cached Long
* Add comments about removing entries from the map
* Pull out bindings for `entry` in IndexShardRoutingTable
* Use .compareTo instead of manually comparing
* add assert for connections not being null and gte to 1
* Copy map for pending search connections instead of "live" map
* Increase the number of pending search requests used for calculating rank when chosen
When a node gets chosen, this increases the number of search counts for the
winning node so that it will not be as likely to be chosen again for
non-concurrent search requests.
* Remove unused HashMap import
* Rename rank -> rankShardsAndUpdateStats
* Rename rankedActiveInitializingShardsIt -> activeInitializingShardsRankedIt
* Instead of precalculating winning node, use "winning" shard from ranked list
* Sort null ranked nodes before nodes that have a rank
At current, we do not feel there is enough of a reason to shade the low
level rest client. It caused problems with commons logging and IDE's
during the brief time it was used. We did not know exactly how many
users will need this, and decided that leaving shading out until we
gather more information is best. Users can still shade the jar
themselves. For information and feeback, see issue #26366.
Closes#26328
This reverts commit 3a20922046.
This reverts commit 2c271f0f22.
This reverts commit 9d10dbea39.
This reverts commit e816ef89a2.
This allows plugins to plug rescore implementations into
Elasticsearch. While this is a fairly expert thing to do I've
done my best to point folks to the QueryRescorer as one that at
least documents the tradeoffs that it makes. I've attempted to
limit the API surface area by removing `SearchContext` from the
exposed interface, instead exposing just the IndexSearcher and
`QueryShardContext`. I also tried to make some of the class names
more consistent and do some general cleanup while I was there.
I entertained the notion of moving the `QueryRescorer` to module.
After all, it'd be a wonderful test to prove that you can plug
rescore implementation into Elasticsearch if the only built in
rescore implementation is in the module. But I decided against it
because the new module would require a client jar and it'd require
moving some more things around. I think if we really want to do
it, we should do it as a followup.
I did, on the other hand, create an "example" rescore plugin which
should both be a nice example for anyone wanting to plug in their
own rescore implementation and servers as a good integration test
to make sure that you can indeed plug one in.
Closes#26208
This PR begins the long journey to deprecating Streamable.
The idea here is to add additional method signatures that
support Writeable.Reader, so that the work to migrate objects TransportMessage to
implement Writeable and not Streamable.
One example conversion is done in this PR: SimulatePipelineRequest.
This commit makes the security code aware of the Java 9 FilePermission changes (see #21534) and allows us to remove the `jdk.io.permissionsUseCanonicalPath` system property.
This commit converts script query to use a new FilterScript context. The
new context returns a boolean, so the error that would have previously
happened at runtime if a non boolean was returned would now happen at
script compilation. Also, the leniency of supporting returning a number
and 0 mapping to false, non-zero to true is gone, but it was never
documented. With the new context compilation will now also fail if
special variables are used at compilation time, instead of runtime, eg
ctx.
Right now we use a custom future for the CloseFuture associated with a
channel. This is because we need special unwrapping logic to ensure that
exceptions from a future failure are a certain type (opposed to an
UncategorizedException). However, the current version is limiting
because we can only attach one listener.
This commit changes the CloseFuture to extend the
PlainListenableActionFuture. This change allows us to attach multiple
listeners.
The client sniffer depends on the low-level REST client, while the Java high-level REST client and the transport client depend on Elasticsearch itself. Javadoc are not that useful unless they have links to the Elasticsearch classes in the latter case, and to the low-level REST client in the sniffer javadoc. This commit adds those links.
This chance adds several random test infrastructure improvements that caused
issues in on-going developments but are generally useful. For instance is it impossible
to restart a node with a secure setting source since we close it after the node is started.
This change makes it cloneable such that we can reuse it for a restart.
The following token filters were moved: arabic_stem, brazilian_stem, czech_stem, dutch_stem, french_stem, german_stem and russian_stem.
Relates to #23658
In reindex APIs, when using the `slices` parameter to choose the number of slices, adds the option to specify `slices` as "auto" which will choose a reasonable number of slices. It uses the number of shards in the source index, up to a ceiling. If there is more than one source index, it uses the smallest number of shards among them.
This gives users an easy way to use slicing in these APIs without having to make decisions about how to configure it, as it provides a good-enough configuration for them out of the box. This may become the default behavior for these APIs in the future.