Pipelines¶

A pipeline is a series of steps that are performed to get benchmark results. This is not intended to customize the actual benchmark but rather what happens before and after a benchmark.

An example will clarify the concept: If you want to benchmark a binary distribution of Elasticsearch, Rally has to download a distribution archive, decompress it, start Elasticsearch and then run the benchmark. However, if you want to benchmark a source build of Elasticsearch, it first has to build a distribution using the Gradle Wrapper. So, in both cases, different steps are involved and that’s what pipelines are for.

You can get a list of all pipelines with esrally list pipelines:

Available pipelines:

Name                     Description
-----------------------  ---------------------------------------------------------------------------------------------
from-sources             Builds and provisions Elasticsearch, runs a benchmark and reports results.
from-sources-complete    Builds and provisions Elasticsearch, runs a benchmark and reports results [deprecated].
from-sources-skip-build  Provisions Elasticsearch (skips the build), runs a benchmark and reports results [deprecated].
from-distribution        Downloads an Elasticsearch distribution, provisions it, runs a benchmark and reports results.
benchmark-only           Assumes an already running Elasticsearch instance, runs a benchmark and reports results

benchmark-only¶

This is intended if you want to provision a cluster by yourself. Do not use this pipeline unless you are absolutely sure you need to. As Rally has not provisioned the cluster, results are not easily reproducable and it also cannot gather a lot of metrics (like CPU usage).

To benchmark a cluster, you also have to specify the hosts to connect to. An example invocation:

esrally --pipeline=benchmark-only --target-hosts=search-node-a.intranet.acme.com:9200,search-node-b.intranet.acme.com:9200

from-distribution¶

This pipeline allows to benchmark an official Elasticsearch distribution which will be automatically downloaded by Rally. The earliest supported version is Elasticsearch 1.7.0. An example invocation:

esrally --pipeline=from-distribution --distribution-version=1.7.5

The version numbers have to match the name in the download URL path.

You can also benchmark Elasticsearch snapshot versions by specifying the snapshot repository:

esrally --pipeline=from-distribution --distribution-version=5.0.0-SNAPSHOT --distribution-repository=snapshot

However, this feature is mainly intended for continuous integration environments and by default you should just benchmark official distributions.

Note

This pipeline is just mentioned for completeness but Rally will autoselect it for you. All you need to do is to define the --distribution-version flag.

from-sources¶

You should use this pipeline when you want to build and benchmark Elasticsearch from sources. This pipeline will only work from Elasticsearch 5.0 onwards because Elasticsearch switched from Maven to Gradle and Rally only supports one build tool in the interest of maintainability.

Remember that you also need git installed. If that’s not the case you’ll get an error and have to run esrally configure first. An example invocation:

esrally --pipeline=from-sources --revision=latest

You have to specify a revision.

Note

This pipeline is just mentioned for completeness but Rally will automatically select it for you. All you need to do is to define the --revision flag.

Artifacts are cached for seven days by default in ~/.rally/benchmarks/distributions/src. Artifact caching can be configured with the following sections in the section source in the configuration file in ~/.rally/rally.ini:

cache (default: True): Set to False to disable artifact caching.
cache.days (default: 7): The maximum age in days of an artifact before it gets evicted from the artifact cache.

from-sources-complete¶

This deprecated pipeline is an alias for from-sources and is only provided for backwards-compatibility. Use from-sources instead.

from-sources-skip-build¶

This deprecated pipeline is similar to from-sources-complete except that it assumes you have built the binary once. Use from-sources instead which caches built artifacts automatically.