Commit Graph

44 Commits

Author SHA1 Message Date
Alexander Reelsen e7868e92bd
Restore date aggregation performance in UTC case (#38221) (#38700)
The benchmarks showed a sharp decrease in aggregation performance for
the UTC case.

This commit uses the same calculation as joda time, which requires no
conversion into any java time object, also, the check for an fixedoffset
has been put into the ctor to reduce the need for runtime calculations.
The same goes for the amount of the used unit in milliseconds.

Closes #37826
2019-02-11 16:30:48 +03:00
Alexander Reelsen 9f026bb8ad
Reduce object creation in Rounding class (#38061)
This reduces objects creations in the rounding class (used by aggs) by properly
creating the objects only once. Furthermore a few unneeded ZonedDateTime objects
were created in order to create other objects out of them. This was
changed as well.

Running the benchmarks shows a much faster performance for all of the
java time based Rounding classes.
2019-01-31 14:18:28 +01:00
Alexander Reelsen b94acb608b
Speed up converting of temporal accessor to zoned date time (#37915)
The existing implementation was slow due to exceptions being thrown if
an accessor did not have a time zone. This implementation queries for
having a timezone, local time and local date and also checks for an
instant preventing to throw an exception and thus speeding up the conversion.

This removes the existing method and create a new one named
DateFormatters.from(TemporalAccessor accessor) to resemble the naming of
the java time ones.

Before this change an epoch millis parser using the toZonedDateTime
method took approximately 50x longer.

Relates #37826
2019-01-31 08:55:40 +01:00
Alexander Reelsen daa2ec8a60
Switch mapping/aggregations over to java time (#36363)
This commit moves the aggregation and mapping code from joda time to
java time. This includes field mappers, root object mappers, aggregations with date
histograms, query builders and a lot of changes within tests.

The cut-over to java time is a requirement so that we can support nanoseconds
properly in a future field mapper.

Relates #27330
2019-01-23 10:40:05 +01:00
Alexander Reelsen 9f3da013d8
Date/Time parsing: Use java time API instead of exception handling (#37222)
* Add benchmark

* Use java time API instead of exception handling

when several formatters are used, the existing way of parsing those is
to throw an exception catch it, and try the next one. This is is
considerably slower than the approach taken in joda time, so that
indexing is reduced when a date format like `x||y` is used and y is the
date format being used.

This commit now uses the java API to parse the date by appending the
date time formatters to each other and does not rely on exception
handling.

* fix benchmark

* fix tests by changing formatter, also expose printer

* restore optional printing logic to fix tests

* fix tests

* incorporate review comments
2019-01-11 09:25:05 +01:00
Alpar Torok a7c3d5842a
Split third party audit exclusions by type (#36763) 2019-01-07 17:24:19 +02:00
Alpar Torok e9ef5bdce8
Converting randomized testing to create a separate unitTest task instead of replacing the builtin test task (#36311)
- Create a separate unitTest task instead of Gradle's built in 
- convert all configuration to use the new task 
- the  built in task is now disabled
2018-12-19 08:25:20 +02:00
Alpar Torok 59b0900174
Upgrade to Gradle 5.0 (#34263) 2018-12-05 14:06:11 +02:00
Nik Everett e28509fbfe
Core: Less settings to AbstractComponent (#35140)
Stop passing `Settings` to `AbstractComponent`'s ctor. This allows us to
stop passing around `Settings` in a *ton* of places. While this change
touches many files, it touches them all in fairly small, mechanical
ways, doing a few things per file:
1. Drop the `super(settings);` line on everything that extends
`AbstractComponent`.
2. Drop the `settings` argument to the ctor if it is no longer used.
3. If the file doesn't use `logger` then drop `extends
AbstractComponent` from it.
4. Clean up all compilation failure caused by the `settings` removal
and drop any now unused `settings` isntances and method arguments.

I've intentionally *not* removed the `settings` argument from a few
files:
1. TransportAction
2. AbstractLifecycleComponent
3. BaseRestHandler

These files don't *need* `settings` either, but this change is large
enough as is.

Relates to #34488
2018-10-31 21:23:20 -04:00
Yannick Welsch 9e522d5d97
Use RUNTIME_JAVA_HOME for micro benchmarks (#34353)
We don't honour RUNTIME_JAVA_HOME for running the benchmarks. It's useful to run some of the
benchmarks against older JDKs, though.
2018-10-08 15:39:00 +02:00
Yannick Welsch 49cbcaff4f
Allow excluding folder names when scanning for dangling indices (#34349)
ES is scanning for dangling indices on every cluster state update. For this, it lists the subfolders of
the indices directory to determine which extra index directories exist on the node where there's no
corresponding index in the cluster state. These are potential targets for dangling index import. On
certain machine types, and with large number of indices, this subfolder listing can be horribly slow.
This means that every cluster state update will be slowed down by potentially hundreds of
milliseconds. One of the reasons for this poor performance is that Files.isDirectory() is a relatively
expensive call on some OS and JDK versions. There is no need though to do all these isDirectory
calls for folders which we know we are going to discard anyhow in the next step of the dangling
indices logic. This commit allows adding an exclusion predicate to the availableIndexFolders
methods which can dramatically speed up this method when scanning for dangling indices.
2018-10-08 15:35:50 +02:00
Alpar Torok 7f7e8fd733
Disable assemble task instead of removing it (#33348) 2018-09-04 07:32:14 +03:00
Nik Everett 21eb9695af
Build: Remove shadowing from benchmarks (#32475)
Removes shadowing from the benchmarks. It isn't *strictly* needed. We do
have to rework the documentation on how to run the benchmark, but it
still seems to work if you run everything through gradle.
2018-07-31 17:31:13 -04:00
Nik Everett 22459576d7
Logging: Make node name consistent in logger (#31588)
First, some background: we have 15 different methods to get a logger in
Elasticsearch but they can be broken down into three broad categories
based on what information is provided when building the logger.

Just a class like:
```
private static final Logger logger = ESLoggerFactory.getLogger(ActionModule.class);
```
or:
```
protected final Logger logger = Loggers.getLogger(getClass());
```

The class and settings:
```
this.logger = Loggers.getLogger(getClass(), settings);
```

Or more information like:
```
Loggers.getLogger("index.store.deletes", settings, shardId)
```

The goal of the "class and settings" variant is to attach the node name
to the logger. Because we don't always have the settings available, we
often use the "just a class" variant and get loggers without node names
attached. There isn't any real consistency here. Some loggers get the
node name because it is convenient and some do not.

This change makes the node name available to all loggers all the time.
Almost. There are some caveats are testing that I'll get to. But in
*production* code the node name is node available to all loggers. This
means we can stop using the "class and settings" variants to fetch
loggers which was the real goal here, but a pleasant side effect is that
the ndoe name is now consitent on every log line and optional by editing
the logging pattern. This is all powered by setting the node name
statically on a logging formatter very early in initialization.

Now to tests: tests can't set the node name statically because
subclasses of `ESIntegTestCase` run many nodes in the same jvm, even in
the same class loader. Also, lots of tests don't run with a real node so
they don't *have* a node name at all. To support multiple nodes in the
same JVM tests suss out the node name from the thread name which works
surprisingly well and easy to test in a nice way. For those threads
that are not part of an `ESIntegTestCase` node we stick whatever useful
information we can get form the thread name in the place of the node
name. This allows us to keep the logger format consistent.
2018-07-31 10:54:24 -04:00
Nik Everett 1b97652a4c
Build: Move shadow customizations into common code (#32014)
Moves the customizations to the build to produce nice shadow jars and
javadocs into common build code, mostly BuildPlugin with a little into
the root build.gradle file. This means that any project that applies the
shadow plugin will automatically be set up just like the high level rest
client:
* The non-shadow jar will not be built
* The shadow jar will not have a "classifier"
* Tests will run against the shadow jar
* Javadoc will include all of the shadowed classes
* Service files in `META-INF/services` will be merged
2018-07-17 14:20:41 -04:00
Daniel Mitterdorfer f174f72fee
Circuit-break based on real memory usage
With this commit we introduce a new circuit-breaking strategy to the parent
circuit breaker. Contrary to the current implementation which only accounts for
memory reserved via child circuit breakers, the new strategy measures real heap
memory usage at the time of reservation. This allows us to be much more
aggressive with the circuit breaker limit so we bump it to 95% by default. The
new strategy is turned on by default and can be controlled  with the new cluster
setting `indices.breaker.total.userealmemory`.

Note that we turn it off for all integration tests with an internal test cluster
because it leads to spurious test failures which are of no value (we cannot
fully control heap memory usage in tests). All REST tests, however, will make
use of the real memory circuit breaker.

Relates #31767
2018-07-13 10:08:28 +02:00
Alpar Torok 8557bbab28
Upgrade gradle wrapper to 4.8 (#31525)
* Move to Gradle 4.8 RC1

* Use latest version of plugin

The current does not work with Gradle 4.8 RC1

* Switch to Gradle GA

* Add and configure build compare plugin

* add work-around for https://github.com/gradle/gradle/issues/5692

* work around https://github.com/gradle/gradle/issues/5696

* Make use of Gradle build compare with reference project

* Make the manifest more compare friendly

* Clear the manifest in compare friendly mode

* Remove animalsniffer from buildscript classpath

* Fix javadoc errors

* Fix doc issues

* reference Gradle issues in comments

* Conditionally configure build compare

* Fix some more doclint issues

* fix typo in build script

* Add sanity check to make sure the test task was replaced

Relates to #31324. It seems like Gradle has an inconsistent behavior and
the taks is not always replaced.

* Include number of non conforming tasks in the exception.

* No longer replace test task, create implicit instead

Closes #31324. The issue has full context in comments.

With this change the `test` task becomes nothing more than an alias for `utest`.
Some of the stand alone tests that had a `test` task now have `integTest`, and a
few of them that used to have `integTest` to run multiple tests now only
have `check`.
This will also help separarate unit/micro tests from integration tests.

* Revert "No longer replace test task, create implicit instead"

This reverts commit f1ebaf7d93e4a0a19e751109bf620477dc35023c.

* Fix replacement of the test task

Based on information from gradle/gradle#5730 replace the task taking
into account the task providres.
Closes #31324.

* Only apply build comapare plugin if needed

* Make sure test runs before integTest

* Fix doclint aftter merge

* PR review comments

* Switch to Gradle 4.8.1 and remove workaround

* PR review comments

* Consolidate task ordering
2018-06-28 08:13:21 +03:00
Alpar Torok 84660ffd5f
Solve Gradle deprecation warnings around shadowJar (#30483)
* Solve Gradle deprecation warnings around shadowJar

- Apply workaround for: johnrengelman/shadow#336
- bump plugin to 2.0.4

Changes between 2.0.2 and 2.0.4 of the plugin:
```
477db40 12 days ago john.engelman@target.com Release 2.0.4
3e3da37 3 weeks ago john.engelman@target.com Remove internal Gradle API and annotation internal getters on shadow jar.
31e2380 3 weeks ago john.engelman@target.com Close input streams. Closes #364
f712cc8 3 weeks ago john.engelman@target.com Upgrade ASM to 6.1.1 to address perf issues. Closes #374
2f94b2b 3 weeks ago john.engelman@target.com next version
23bbf3d 7 weeks ago john.r.engelman@gmail.com Add some gradle versions. Update changelog for 2.0.3
7435c74 7 weeks ago john.r.engelman@gmail.com Merge pull request #367 from ttsiebzehntt/366-java10
325c002 7 weeks ago info@martinsadowski.de Update ASM to 6.1
94550e5 3 months ago john.r.engelman@gmail.com Merge pull request #356 from sgnewson/update-file-to-files
66b691e 4 months ago john.r.engelman@gmail.com Merge pull request #358 from 3flex/patch-1
14761b1 4 months ago 3flex@users.noreply.github.com fix markdown for User Guide URL in issue template
a3f6984 4 months ago newson@synopsys.com update inputs.file to inputs.files, to remove warning
```

closes #30389

* Improove comment as suggested
2018-05-10 12:49:41 +03:00
Daniel Mitterdorfer aeaebddf4a
Honor RUNTIME_JAVA_HOME for benchmarks (#28962)
With this commit we configure our microbenchmarks project to use the
configured RUNTIME_JAVA_HOME and to fallback on JAVA_HOME so this
behavior is consistent  with the rest of the Elasticsearch build.

Closes #28961
2018-03-12 07:58:07 +01:00
Daniel Mitterdorfer 8085ec504b Upgrade Gradle Shadow plugin to 2.0.2
With this commit we upgrade the Gradle Shadow plugin that is used in our
benchmarks to version 2.0.2. This version does not use APIs that are
deprecated in Gradle 4.x.
2017-12-29 10:57:11 +01:00
Maxime Gréau 771defb97c
Build: Add 3rd party dependencies report generation (#27727)
* Adds task dependenciesInfo to BuildPlugin to generate a CSV file with dependencies information (name,version,url,license)
* Adds `ConcatFilesTask.groovy` to concatenates multiple files into one
* Adds task `:distribution:generateDependenciesReport` to concatenate `dependencies.csv` files into a single file (`es-dependencies.csv` by default)

 # Examples:
      $ gradle dependenciesInfo :distribution:generateDependenciesReport

 ## Use `csv` system property to customize the output file path
     $ gradle dependenciesInfo :distribution:generateDependenciesReport -Dcsv=/tmp/elasticsearch-dependencies.csv

 ## When branch is not master, use `build.branch` system property to generate correct licenses URLs
     $ gradle dependenciesInfo :distribution:generateDependenciesReport -Dbuild.branch=6.x -Dcsv=/tmp/elasticsearch-dependencies.csv
2017-12-26 10:51:47 +01:00
Nik Everett 21b1db2965 Remove assemble from build task when assemble removed
Removes the `assemble` task from the `build` task when we have
removed `assemble` from the project. We removed `assemble` from
projects that aren't published so our releases will be faster. But
That broke CI because CI builds with `gradle precommit build` and,
it turns out, that `build` includes `check` and `assemble`. With
this change CI will only run `check` for projects without an
`assemble`.
2017-06-16 17:19:14 -04:00
Nik Everett 7b358190d6 Remove assemble task when not used for publishing (#25228)
Removes the `assemble` task from projects that are not published.
This should speed up `gradle assemble` by skipping projects that
don't need to be built. Which is useful because `gradle assemble`
is how we cut releases.
2017-06-16 11:46:34 -04:00
Yannick Welsch c8712e9531 Limit AllocationService dependency injection hack (#24479)
Changes the scope of the AllocationService dependency injection hack so that it is at least contained to the AllocationService and does not leak into the Discovery world.
2017-05-05 08:39:18 +02:00
Ryan Ernst 175bda64a0 Build: Rework integ test setup and shutdown to ensure stop runs when desired (#23304)
Gradle's finalizedBy on tasks only ensures one task runs after another,
but not immediately after. This is problematic for our integration tests
since it allows multiple project's integ test clusters to be
simultaneously. While this has not been a problem thus far (gradle 2.13
happened to keep the finalizedBy tasks close enough that no clusters
were running in parallel), with gradle 3.3 the task graph generation has
changed, and numerous clusters may be running simultaneously, causing
memory pressure, and thus generally slower tests, or even failure if the
system has a limited amount of memory (eg in a vagrant host).

This commit reworks how integ tests are configured. It adds an
`integTestCluster` extension to gradle which is equivalent to the current
`integTest.cluster` and moves the rest test runner task to
`integTestRunner`.  The `integTest` task is then just a dummy task,
which depends on the cluster runner task, as well as the cluster stop
task. This means running `integTest` in one project will both run the
rest tests, and shut down the cluster, before running `integTest` in
another project.
2017-02-22 12:43:15 -08:00
Yannick Welsch 0035f5ab95 Fix compilation of benchmarks on JDK 9
The JDK 9 compiler (b151) emits the warning "No processor claimed any of these annotations" for annotations that would be runtime annotation. Maybe a
regression from https://bugs.openjdk.java.net/browse/JDK-8039469. This is a quick fix so that compilation works again.
2017-01-06 16:50:43 +01:00
Daniel Mitterdorfer b2aaeb56f3 Update JMH to 1.17.3 2016-12-19 10:02:42 +01:00
Daniel Mitterdorfer e38f06cdc6 Update Gradle shadow plugin for microbenchmarks to 1.2.4 2016-12-19 10:02:42 +01:00
Daniel Mitterdorfer 087a931cb2 Use 'pipe' instead of of 'comma' to separate benchmark params
With this commit we separate benchmark parameters with pipe symbols
instead of commas as JMH has a special formatting logic for comma-separated
string which messes up the JSON output of microbenchmarks.
2016-10-10 14:56:44 +02:00
Simon Willnauer 194a6b1df0 Remove LocalTransport in favor of MockTcpTransport (#20695)
This change proposes the removal of all non-tcp transport implementations. The
mock transport can be used by default to run tests instead of local transport that has
roughly the same performance compared to TCP or at least not noticeably slower.

This is a master only change, deprecation notice in 5.x will be committed as a
separate change.
2016-10-07 11:27:47 +02:00
Ali Beyad ac1b13dde7 Changes the API of GatewayAllocator#applyStartedShards and (#20642)
Changes the API of GatewayAllocator#applyStartedShards and 
GatewayAllocator#applyFailedShards to take both a RoutingAllocation
and a list of shards to apply. This allows better mock allocators
to be created as being done in #20637.

Closes #20642
2016-09-23 09:31:46 -04:00
Ali Beyad 029fc909b5 Removes FailedRerouteAllocation and StartedRerouteAllocation
Removes the FailedRerouteAllocation class and StartedRerouteAllocation
class, as they were just wrappers for RerouteAllocation that stored
started and failed shards, but these started and failed shards can
be passed in directly to the methods that needed them, removing the
need for this wrapper class and extra level of indirection.

Closes #20626
2016-09-23 09:02:36 -04:00
Daniel Mitterdorfer 9d8961aeb9 Provide log4j2 logging config for microbenchmarks 2016-09-19 14:28:16 +02:00
Boaz Leskes 2ee9ab25d9 Remove `RoutingAllocation.Result` (#20538)
Currently all the reroute-like methods of `AllocationService` return a result object of type `RoutingAllocation.Result`. The result object contains the new `RoutingTable` and `MetaData` plus an indication whether those were changed. The caller is then responsible of updating a cluster state with these. These means that things can easily go wrong and one can take one of these but not the other causing inconsistencies. We already have a utility method on the `ClusterState` builder that does but no one forces you to do so. Also 99% of the callers do the same thing: i.e., check if the result was changed and if so update the very same cluster state that was passed to `AllocationService`.  This PR folds this pattern into `AllocationService` and changes almost all it's methods to return a new cluster state (potentially the original one).  This saves some 500 lines of code.

The one exception here is the reroute API which executes allocation commands and potentially returns an explanation as well (next to the routing table and metadata). That API now returns a `CommandsResult` object which encapsulate a cluster state and the explanation.
2016-09-19 13:54:35 +02:00
Daniel Mitterdorfer c13513ed61 Allow to enable annotation processing explicitly (#20117)
In 1e91f3b we disabled annotation processors globally. However, some
project like JMH need annotation processing, so we add an ability to
selectively enabled annotation processing for certain projects by
setting an external property in the corresponding Gradle build script.

Note that `javac` would allow to set a specific annotation processor
with the command line option `-processor`. However, due to a bug in
Gradle we we cannot use this option and need to enable all annotation
processors.
2016-08-23 15:15:22 +02:00
Ryan Ernst 1ff348ed7f Plugins: Make custom allocation deciders use pull based extensions
This change converts AllocationDecider registration from push based on
ClusterModule to implementing with a new ClusterPlugin interface.
AllocationDecider instances are allowed to use only Settings and
ClusterSettings.
2016-08-17 15:55:31 -07:00
Yannick Welsch 27a760f9c1 Add routing changes API to RoutingAllocation (#19992)
Adds a class that records changes made to RoutingAllocation, so that at the end of the allocation round other values can be more easily derived based on these changes. Most notably, it:

- replaces the explicit boolean flag that is passed around everywhere to denote changes to the routing table. The boolean flag is automatically updated now when changes actually occur, preventing issues where it got out of sync with actual changes to the routing table.
- records actual changes made to RoutingNodes so that primary term and in-sync allocation ids, which are part of index metadata, can be efficiently updated just by looking at the shards that were actually changed.
2016-08-17 10:46:59 +02:00
Boaz Leskes 609a199bd4 Upon being elected as master, prefer joins' node info to existing cluster state (#19743)
When we introduces [persistent node ids](https://github.com/elastic/elasticsearch/pull/19140) we were concerned that people may copy data folders from one to another resulting in two nodes competing for the same id in the cluster. To solve this we elected to not allow an incoming join if a different with same id already exists in the cluster, or if some other node already has the same transport address as the incoming join. The rationeel there was that it is better to prefer existing nodes and that we can rely on node fault detection to remove any node from the cluster that isn't correct any more, making room for the node that wants to join (and will keep trying).

Sadly there were two problems with this:
1) One minor and easy to fix - we didn't allow for the case where the existing node can have the same network address as the incoming one, but have a different ephemeral id (after node restart). This confused the logic in `AllocationService`, in this rare cases. The cluster is good enough to detect this and recover later on, but it's not clean.
2) The assumption that Node Fault Detection will clean up is *wrong* when the node just won an election (it wasn't master before) and needs to process the incoming joins in order to commit the cluster state and assume it's mastership. In those cases, the Node Fault Detection isn't active. 

This PR fixes these two and prefers incoming nodes to existing node when finishing an election. 
On top of the, on request by @ywelsch , `AllocationService` synchronization between the nodes of the cluster and it's routing table is now explicit rather than something we do all the time. The same goes for promotion of replicas to primaries.
2016-08-05 08:58:03 +02:00
Boaz Leskes 6861d3571e Persistent Node Ids (#19140)
Node IDs are currently randomly generated during node startup. That means they change every time the node is restarted. While this doesn't matter for ES proper, it makes it hard for external services to track nodes. Another, more minor, side effect is that indexing the output of, say, the node stats API results in creating new fields due to node ID being used as keys.

The first approach I considered was to use the node's published address as the base for the id. We already [treat nodes with the same address as the same](https://github.com/elastic/elasticsearch/blob/master/core/src/main/java/org/elasticsearch/discovery/zen/NodeJoinController.java#L387) so this is a simple change (see [here](https://github.com/elastic/elasticsearch/compare/master...bleskes:node_persistent_id_based_on_address)). While this is simple and it works for probably most cases, it is not perfect. For example, if after a node restart, the node is not able to bind to the same port (because it's not yet freed by the OS), it will cause the node to still change identity. Also in environments where the host IP can change due to a host restart, identity will not be the same. 

Due to those limitation, I opted to go with a different approach where the node id will be persisted in the node's data folder. This has the upside of connecting the id to the nodes data. It also means that the host can be adapted in any way (replace network cards, attach storage to a new VM). I

It does however also have downsides - we now run the risk of two nodes having the same id, if someone copies clones a data folder from one node to another. To mitigate this I changed the semantics of the protection against multiple nodes with the same address to be stricter - it will now reject the incoming join if a node exists with the same id but a different address. Note that if the existing node doesn't respond to pings (i.e., it's not alive) it will be removed and the new node will be accepted when it tries another join.

Last, and most importantly, this change requires that *all* nodes persist data to disk. This is a change from current behavior where only data & master nodes store local files. This is the main reason for marking this PR as breaking.

Other less important notes:
- DummyTransportAddress is removed as we need a unique network address per node. Use `LocalTransportAddress.buildUnique()` instead.
- I renamed `node.add_lid_to_custom_path` to `node.add_lock_id_to_custom_path` to avoid confusion with the node ID which is now part of the `NodeEnvironment` logic.
- I removed the `version` paramater from `MetaDataStateFormat#write` , it wasn't really used and was just in the way :)
- TribeNodes are special in the sense that they do start multiple sub-nodes (previously known as client nodes). Those sub-nodes do not store local files but derive their ID from the parent node id, so they are generated consistently.
2016-07-04 21:09:25 +02:00
Simon Willnauer bdb6dcea3a Cleanup ClusterService dependencies and detached from Guice (#18941)
This change removes some unnecessary dependencies from ClusterService
and cleans up ClusterName creation. ClusterService is now not created
by guice anymore.
2016-06-17 17:07:19 +02:00
Daniel Mitterdorfer 889d802115 Refine wording in benchmark README and correct typos 2016-06-15 23:01:56 +02:00
Daniel Mitterdorfer 32dd813436 Fix typo in benchmark README 2016-06-15 22:45:47 +02:00
Daniel Mitterdorfer d56e4bc7b1 Remove obsolete benchmarks / comments 2016-06-15 16:54:54 +02:00
Daniel Mitterdorfer 2c467fd9c2 Add microbenchmarking infrastructure (#18891)
With this commit we add a benchmarks project that contains the necessary build
infrastructure and an example benchmark. It is added as a separate project to avoid
interfering with the regular build too much (especially sanity checks) and to keep
the microbenchmarks isolated.

Microbenchmarks are generated with `gradle :benchmarks:jmhJar` and can be run with
` gradle :benchmarks:jmh`.

We intentionally do not use the
[jmh-gradle-plugin](https://github.com/melix/jmh-gradle-plugin) as it causes all
sorts of problems (dependencies are not properly excluded, not all JMH parameters
can be set) and it adds another abstraction layer that is not needed.

Closes #18242
2016-06-15 16:48:02 +02:00