Smoke Tests

Test Organization

  • dbtests/.*cpp has old-style C++ unit tests
  • jstests/*.js has core tests
  • jstests/repl*/*.js has replication tests
  • jstests/sharding/*.js has sharding tests
  • slowNightly/*js has tests that take longer and run only at night
  • slowWeekly/*.js has tests that take even longer and run only once a week

Running all the tests

scons smoke smokeCppUnittests smokeDisk smokeTool smokeAuth startMongod smokeClient smokeJs
scons startMongodSmallOplog smokeJs
scons startMongod smokeJsSlowNightly
scons smokeTool
scons smokeReplSets
scons smokeDur
scons mongosTest smokeSharding
scons smokeRepl smokeClone
scons startMongod smokeParallel


smoke.py lets you run a subsets of the tests in jstests/. When it is running tests, it starts up an instance of mongod, runs the tests, and then shuts it down again. You can run it while running other instances of MongoDB on the same machine: it uses ports in the 30000 range and its own data directories.

For the moment, smoke.py must be run from the top-level directory of a MongoDB source repository. This directory must contain at least the mongo and mongod binaries. To run certain tests, you’ll also need to build the tools and mongos. It’s a good idea to run scons . before running the tests.

To run smoke.py you’ll need a recent version of PyMongo.

To see the possible options, run:

$ python buildscripts/smoke.py --help
Usage: smoke.py [OPTIONS] ARGS*

  -h, --help            show this help message and exit
  --mode=MODE           If "files", ARGS are filenames; if "suite", ARGS are
                        sets of tests (suite)
                        Path to the test executables to run, currently only
                        used for 'client' (none)
                        Path to mongod to run (/Users/mike/mongo/mongod)
  --port=MONGOD_PORT    Port the mongod will bind to (32000)
                        Path to mongo, for .js test files
                        If supplied, continue testing even after a test fails
  --from-file=FILE      Run tests/suites named in FILE, one test per line, '-'
                        means stdin
                        Prefix to use for the mongods' dbpaths ('')
  --small-oplog         Run tests with master/slave replication & use a small


By default, smoke.py will run tests that create data in /data/db, which may interfere with other MongoDB instances you are running. To change the directory in which the smoke tests create databases, use --smoke-db-prefix=/some/other/path

To run specific tests, use the --mode=files option:

python buildscripts/smoke.py --mode=files jstests/find1.js

You can specify as many files as you want.

You can also run a suite of tests. Suites are predefined and include:

  • test
  • all
  • perf
  • js
  • quota
  • jsPerf
  • disk
  • jsSlowNightly
  • jsSlowWeekly
  • parallel
  • clone
  • repl (master/slave replication tests)
  • replSets (replica set tests)
  • auth
  • sharding
  • tool
  • client
  • mongosTest

To run a suite, specify the suite’s name:

python buildscripts/smoke.py js

Running a jstest manually

You can run a jstest directly from the shell, for example:

mongo --nodb jstests/replsets/replsetarb3.js

Running the C++ unit tests

The tests under jstests/ folder are written in mongo shell javascript. However there are a set of C++ unit tests also. To run them:

scons test

Build the unit tests (in src/mongo/unittest/ by running:

$ scons build/unittests.txt
/* build output */
Generating build/unittests.txt
scons: done building targets.

Then use the line above to run the binary generated:

$ ./build/linux2/dd/durableDefaultOff/mongo/platform/atomic_word_test


On OS X, the C++ unit tests will not pass unless you increase the file descriptor limit. To temporally change this setting issue the following command:

ulimit -n 2048

You can persist this change with the following command:

launchctl limit maxfiles 2048 2048

See UNIX ulimit Settings for more information.

See also