rake parallel:create 

rake parallel:prepare 

rake parallel:setup 

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 ... 

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 rake parallel:spec['spec\/(?!features)'] # run RSpec tests except the tests in spec/features 

2 processes for 210 specs, ~ 105 specs per process ... test output ... 843 examples, 0 failures, 1 pending Took 29.925333 seconds 

--format progress --format ParallelTests::RSpec::RuntimeLogger --out tmp/parallel_runtime_rspec.log 

--format progress --format ParallelTests::RSpec::SummaryLogger --out tmp/spec_summary.log 

rspec /path/to/my_spec.rb:123 # should do something 

--format progress --format ParallelTests::RSpec::FailuresLogger --out tmp/failing_specs.log 

cucumber --format ParallelTests::Cucumber::FailuresLogger --out tmp/cucumber_failures.log 

parallel: --format progress --format ParallelTests::Cucumber::FailuresLogger --out tmp/cucumber_failures.log 

cucumber @tmp/cucumber_failures.log 

gem install parallel_tests # go to your project dir parallel_test test/ parallel_rspec spec/ parallel_cucumber features/ parallel_spinach features/ 

-n [PROCESSES] How many processes to use, default: available CPUs -p, --pattern [PATTERN] run tests matching this regex pattern --exclude-pattern [PATTERN] exclude tests matching this regex 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 --prefix-output-with-test-env-number Prefixes test env number to the output when not using --serialize-stdout --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 debug output --verbose-process-command Print the command that will be executed by each process before it begins --verbose-rerun-command After a process fails, print the command executed by that process --quiet Print only test output -v, --version Show Version -h, --help Show this. 

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"