# parallel_tests [![Gem Version](https://badge.fury.io/rb/parallel_tests.svg)](https://rubygems.org/gems/parallel_tests) [![Build Status](https://travis-ci.org/grosser/parallel_tests.svg)](https://travis-ci.org/grosser/parallel_tests/builds) Speedup Test::Unit + RSpec + Cucumber + Spinach by running parallel on multiple CPU cores.
ParallelTests splits tests into even groups (by number of lines or runtime) and runs each group in a single process with its own database. Setup for Rails =============== [RailsCasts episode #413 Fast Tests](http://railscasts.com/episodes/413-fast-tests) ### Install ```ruby # Gemfile gem "parallel_tests", group: :development ``` ### Add to `config/database.yml` ParallelTests uses 1 database per test-process.
Process number123
ENV['TEST_ENV_NUMBER']'''2''3'
```yaml test: database: yourproject_test<%= ENV['TEST_ENV_NUMBER'] %> ``` ### Create additional database(s) rake parallel:create ### Copy development schema (repeat after migrations) rake parallel:prepare ### Run! rake parallel:test # Test::Unit rake parallel:spec # RSpec rake parallel:features # Cucumber rake parallel:features-spinach # Spinach rake parallel:test[1] --> force 1 CPU --> 86 seconds rake parallel:test --> got 2 CPUs? --> 47 seconds rake parallel:test --> got 4 CPUs? --> 26 seconds ... Test by pattern (e.g. use one integration server per subfolder / see if you broke any 'user'-related tests) rake parallel:test[^test/unit] # every test file in test/unit folder rake parallel:test[user] # run users_controller + user_helper + user tests rake parallel:test['user|product'] # run user and product related tests ### Example output 2 processes for 210 specs, ~ 105 specs per process ... test output ... 843 examples, 0 failures, 1 pending Took 29.925333 seconds ### Run an arbitrary task in parallel ```Bash RAILS_ENV=test parallel_test -e "rake my:custom:task" # or rake parallel:rake[my:custom:task] # limited parallelism rake parallel:rake[my:custom:task,2] ``` Running things once =================== ```Ruby # effected by race-condition: first process may boot slower the second # either sleep a bit or use a lock for example File.lock ParallelTests.first_process? ? do_something : sleep(1) at_exit do if ParallelTests.first_process? ParallelTests.wait_for_other_processes_to_finish undo_something end end ``` Loggers =================== Even test group run-times ------------------------- ### RSpec Add the `RuntimeLogger` to log how long each test takes to run. This log file will be loaded on the next test run, and the tests will be grouped so that each process should finish around the same time. Rspec: Add to your `.rspec_parallel` (or `.rspec`) : --format progress --format ParallelTests::RSpec::RuntimeLogger --out tmp/parallel_runtime_rspec.log ### Test::Unit & Minitest 4/5 Add to your `test_helper.rb`: ```ruby require 'parallel_tests/test/runtime_logger' if ENV['RECORD_RUNTIME'] ``` results will be logged to tmp/parallel_runtime_test.log when `RECORD_RUNTIME` is set, so it is not always required or overwritten. RSpec: SummaryLogger -------------------- Log the test output without the different processes overwriting each other. Add the following to your `.rspec_parallel` (or `.rspec`) : --format progress --format ParallelTests::RSpec::SummaryLogger --out tmp/spec_summary.log RSpec: FailuresLogger ----------------------- Produce pasteable command-line snippets for each failed example. E.g. rspec /path/to/my_spec.rb:123 # should do something Add the following to your `.rspec_parallel` (or `.rspec`) : --format progress --format ParallelTests::RSpec::FailuresLogger --out tmp/failing_specs.log Cucumber: FailuresLogger ----------------------- Log failed cucumber scenarios to the specified file. The filename can be passed to cucumber, prefixed with '@' to rerun failures. Usage: cucumber --format ParallelTests::Cucumber::FailuresLogger --out tmp/cucumber_failures.log Or add the formatter to the `parallel:` profile of your `cucumber.yml`: parallel: --format progress --format ParallelTests::Cucumber::FailuresLogger --out tmp/cucumber_failures.log Note if your `cucumber.yml` default profile uses `<%= std_opts %>` you may need to insert this as follows `parallel: <%= std_opts %> --format progress...` To rerun failures: cucumber @tmp/cucumber_failures.log Setup for non-rails =================== gem install parallel_tests # go to your project dir parallel_test test/ parallel_rspec spec/ parallel_cucumber features/ parallel_spinach features/ - use `ENV['TEST_ENV_NUMBER']` inside your tests to select separate db/memcache/etc. - Only run selected files & folders: `parallel_test test/bar test/baz/foo_text.rb` - Pass test-options and files via `--`: `parallel_test -- -t acceptance -f progress -- spec/foo_spec.rb spec/acceptance` Options are: -n [PROCESSES] How many processes to use, default: available CPUs -p, --pattern [PATTERN] run tests matching this pattern --group-by [TYPE] group tests by: found - order of finding files steps - number of cucumber/spinach steps scenarios - individual cucumber scenarios filesize - by size of the file runtime - info from runtime log default - runtime when runtime log is filled otherwise filesize -m, --multiply-processes [FLOAT] use given number as a multiplier of processes to run -s, --single [PATTERN] Run all matching files in the same process -i, --isolate Do not run any other tests in the group used by --single(-s) --only-group INT[, INT] -e, --exec [COMMAND] execute this code parallel and with ENV['TEST_ENV_NUMBER'] -o, --test-options '[OPTIONS]' execute test commands with those options -t, --type [TYPE] test(default) / rspec / cucumber / spinach --suffix [PATTERN] override built in test file pattern (should match suffix): '_spec.rb$' - matches rspec files '_(test|spec).rb$' - matches test or spec files --serialize-stdout Serialize stdout output, nothing will be written until everything is done --combine-stderr Combine stderr into stdout, useful in conjunction with --serialize-stdout --non-parallel execute same commands but do not in parallel, needs --exec --no-symlinks Do not traverse symbolic links to find test files --ignore-tags [PATTERN] When counting steps ignore scenarios with tags that match this pattern --nice execute test commands with low priority. --runtime-log [PATH] Location of previously recorded test runtimes --allowed-missing Allowed percentage of missing runtimes (default = 50) --unknown-runtime [FLOAT] Use given number as unknown runtime (otherwise use average time) --verbose Print more output -v, --version Show Version -h, --help Show this. You can run any kind of code in parallel with -e / --exec parallel_test -n 5 -e 'ruby -e "puts %[hello from process #{ENV[:TEST_ENV_NUMBER.to_s].inspect}]"' hello from process "2" hello from process "" hello from process "3" hello from process "5" hello from process "4"
1 Process2 Processes4 Processes
RSpec spec-suite18s14s10s
Rails-ActionPack88s53s44s
TIPS ==== - `--first-is-1` or `export PARALLEL_TEST_FIRST_IS_1=true` will make the first environment be `1`, so you can test while running your full suite - Debug errors that only happen with multiple files using `--verbose` and [cleanser](https://github.com/grosser/cleanser) - [RSpec] add a `.rspec_parallel` to use different options, e.g. **no --drb** - [RSpec] remove `--loadby` from `.rspec` - [RSpec] Instantly see failures (instead of just a red F) with [rspec-instafail](https://github.com/grosser/rspec-instafail) - [RSpec] use [rspec-retry](https://github.com/NoRedInk/rspec-retry) (not rspec-rerun) to rerun failed tests. - [Cucumber] add a `parallel: foo` profile to your `config/cucumber.yml` and it will be used to run parallel tests - [Capybara setup](https://github.com/grosser/parallel_tests/wiki) - [Sphinx setup](https://github.com/grosser/parallel_tests/wiki) - [Capistrano setup](https://github.com/grosser/parallel_tests/wiki/Remotely-with-capistrano) let your tests run on a big box instead of your laptop - [SQL schema format] use :ruby schema format to get faster parallel:prepare` - [ZSH] use quotes to use rake arguments `rake "parallel:prepare[3]"` - [email_spec and/or action_mailer_cache_delivery](https://github.com/grosser/parallel_tests/wiki) - [Memcached] use different namespaces e.g. `config.cache_store = ..., namespace: "test_#{ENV['TEST_ENV_NUMBER']}"` - [zeus-parallel_tests](https://github.com/sevos/zeus-parallel_tests) - [Distributed parallel test (e.g. Travis Support)](https://github.com/grosser/parallel_tests/wiki/Distributed-Parallel-Tests-and-Travis-Support) - `export PARALLEL_TEST_PROCESSORS=13` to override default processor count - Shell alias: `alias prspec='parallel_rspec -m 2 --'` - [Spring] to use spring you have to [patch it](https://github.com/grosser/parallel_tests/wiki/Spring) - Contribute your own gotaches to the [Wiki](https://github.com/grosser/parallel_tests/wiki) or even better open a PR :) TODO ==== - fix tests vs cucumber >= 1.2 `unknown option --format` - add unit tests for cucumber runtime formatter - make windows compatible Authors ==== inspired by [pivotal labs](https://blog.pivotal.io/labs/labs/parallelize-your-rspec-suite) ### [Contributors](https://github.com/grosser/parallel_tests/contributors) - [Charles Finkel](http://charlesfinkel.com/) - [Indrek Juhkam](http://urgas.eu) - [Jason Morrison](http://jayunit.net) - [jinzhu](http://github.com/jinzhu) - [Joakim Kolsjö](http://www.rubyblocks.se) - [Kevin Scaldeferri](http://kevin.scaldeferri.com/blog/) - [Kpumuk](http://kpumuk.info/) - [Maksim Horbul](http://github.com/mhorbul) - [Pivotal Labs](http://www.pivotallabs.com) - [Rohan Deshpande](http://github.com/rdeshpande) - [Tchandy](http://thiagopradi.net/) - [Terence Lee](http://hone.heroku.com/) - [Will Bryant](http://willbryant.net/) - [Fred Wu](http://fredwu.me) - [xxx](https://github.com/xxx) - [Levent Ali](http://purebreeze.com/) - [Michael Kintzer](https://github.com/rockrep) - [nathansobo](https://github.com/nathansobo) - [Joe Yates](http://titusd.co.uk) - [asmega](http://www.ph-lee.com) - [Doug Barth](https://github.com/dougbarth) - [Geoffrey Hichborn](https://github.com/phene) - [Trae Robrock](https://github.com/trobrock) - [Lawrence Wang](https://github.com/levity) - [Sean Walbran](https://github.com/seanwalbran) - [Lawrence Wang](https://github.com/levity) - [Potapov Sergey](https://github.com/greyblake) - [Łukasz Tackowiak](https://github.com/lukasztackowiak) - [Pedro Carriço](https://github.com/pedrocarrico) - [Pablo Manrubia Díez](https://github.com/pmanrubia) - [Slawomir Smiechura](https://github.com/ssmiech) - [Georg Friedrich](https://github.com/georg) - [R. 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License: MIT