c776550b58
The snapshot TTL is applied to the snapshot manifest.json as the `expires_at` attribute. It will be used in the future by an external service like scylla-manager or siren to manage the snapshot life cycle. In Scylla, it is used just to garbage collect orphaned snapshots that were not backed up and cleaned up in time. A garbage collector thread was added to snapshot_ctl that cleans up the snapshot when it expires. The series adds 2 paths setting the snapshot ttl: - db/config: add auto_snapshot_ttl - api, nodetool: add snapshot ttl option The new functionality in Scylla is comparable to the corresponding features in Cassandra (comparison based on https://github.com/scylladb/scylladb/issues/13409): 1) Cassandra added in release 4.1 the auto_snapshot_ttl option which is described in [cassandra.apache.org/doc/latest/cassandra/configuration/cass_yaml_file.html#auto_snapshot_ttl](https://cassandra.apache.org/doc/latest/cassandra/configuration/cass_yaml_file.html#auto_snapshot_ttl) as: > Adds a time-to-live (TTL) to auto snapshots generated by table truncation or drop (when enabled). After the TTL is elapsed, the snapshot is automatically cleared. The behavior is now the same in Scylla > By default, auto snapshots do not have TTL In scylla, existing clusters will have no auto_snapshot_ttl, however new clusters installed with the updated scylla.conf will have a default auto_snapshot_ttl of 10 days (864000 seconds) > Accepted units: d (days), h (hours) or m (minutes) The configuration option is always in seconds, no support for unit suffix. TTL values passed to the api directly or via and nodetool can be optionally followed by 's' for seconds (the default), 'm' for minutes, 'h' for hours, or 'd' for days. > [issues.apache.org/jira/browse/CASSANDRA-16789](https://issues.apache.org/jira/browse/CASSANDRA-16789), commitad24942481- add a thread that every minute checks to see if there are TTLed snapshots to be deleted, and also add support in nodetool. In scylla, the background thread wakes up if there are scheduled expirations. Clearing of expired snapshots on restart is not implemented yet. > This is for automatically-created snapshots. Additionally, Cassandra added the ability to set a ttl on manually created snapshots by the nodetool snapshot command - by adding a --ttl ...option to that command. The equivalent functionality is to pass a --ttl option when taking a snapshot. There is no support to set a TTL on an existing snapshot (nor there is a plan to do so). > `nodetool listsnapshots` was also updated to list the snapshots' TTLs. See [issues.apache.org/jira/browse/CASSANDRA-16789](https://issues.apache.org/jira/browse/CASSANDRA-16789), commitad24942481. TODO, see https://scylladb.atlassian.net/browse/SCYLLADB-1078 Fixes SCYLLADB-190 Fixes SCYLLADB-191 Fixes SCYLLADB-787 Fixes SCYLLADB-789 * New feature, no backport required Closes scylladb/scylladb#28759 * github.com:scylladb/scylladb: db: snapshot-ctl: add cancel_expiration api, nodetool: add snapshot ttl option test/cqlpy/test_virtual_tables: add verfication of snapshot directory test/cqlpy/test_virtual_tables: consistenly pass a set of expected tables to verify_snapshots db: snapshot_ctl: add deletion of expired snapshots database: apply auto_snapshot_ttl db/config: add auto_snapshot_ttl db/config: make auto_snapshot live-updateable
Scylla unit tests using C++ and the Boost test framework
The source files in this directory are Scylla unit tests written in C++ using the Boost.Test framework. These unit tests come in three flavors:
-
Some simple tests that check stand-alone C++ functions or classes use Boost's
BOOST_AUTO_TEST_CASE. -
Some tests require Seastar features, and need to be declared with Seastar's extensions to Boost.Test, namely
SEASTAR_TEST_CASE. -
Even more elaborate tests require not just a functioning Seastar environment but also a complete (or partial) Scylla environment. Those tests use the
do_with_cql_env()ordo_with_cql_env_thread()function to set up a mostly-functioning environment behaving like a single-node Scylla, in which the test can run.
While we have many tests of the third flavor, writing new tests of this type should be reserved to white box tests - tests where it is necessary to inspect or control Scylla internals that do not have user-facing APIs such as CQL. In contrast, black-box tests - tests that can be written only using user-facing APIs, should be written in one of newer test frameworks that we offer - such as test/cqlpy or test/alternator (in Python, using the CQL or DynamoDB APIs respectively) or test/cql (using textual CQL commands), or - if more than one Scylla node is needed for a test - using the test/topology* framework.
Running tests
Because these are C++ tests, they need to be compiled before running.
To compile a single test executable row_cache_test, use a command like
ninja build/dev/test/boost/row_cache_test
You can also use ninja dev-test to build all C++ tests, or use
ninja deb-build to build the C++ tests and also the full Scylla executable
(however, note that full Scylla executable isn't needed to run Boost tests).
Replace "dev" by "debug" or "release" in the examples above and below to use the "debug" build mode (which, importantly, compiles the test with ASAN and UBSAN enabling on and helps catch difficult-to-catch use-after-free bugs) or the "release" build mode (optimized for run speed).
To run an entire test file row_cache_test, including all its test
functions, use a command like:
build/dev/test/boost/row_cache_test -- -c1 -m1G
to run a single test function test_reproduce_18045() from the longer test
file, use a command like:
build/dev/test/boost/row_cache_test -t test_reproduce_18045 -- -c1 -m1G
In these command lines, the parameters before the -- are passed to
Boost.Test, while the parameters after the -- are passed to the test code,
and in particular to Seastar. In this example Seastar is asked to run on one
CPU (-c1) and use 1G of memory (-m1G) instead of hogging the entire
machine. The Boost.Test option -t test_reproduce_18045 asks it to run just
this one test function instead of all the test functions in the executable.
Unfortunately, interrupting a running test with control-C while doesn't
work. This is a known bug (#5696). Kill a test with SIGKILL (-9) if you
need to kill it while it's running.
Boost tests can also be run using test.py - which is a script that provides a uniform way to run all tests in scylladb.git - C++ tests, Python tests, etc.
Execution with pytest
To run all tests with pytest execute
pytest test/boost
To execute all tests in one file, provide the path to the source filename as a parameter
pytest test/boost/aggregate_fcts_test.cc
Since it's a normal path, autocompletion works in the terminal out of the box.
To execute only one test function, provide the path to the source file and function name
pytest --mode dev test/boost/aggregate_fcts_test.cc::test_aggregate_avg
To provide a specific mode, use the next parameter --mode dev,
if parameter isn't provided pytest tries to use ninja mode_list to find out the compiled modes.
Parallel execution is controlled by pytest-xdist and the parameter -n auto.
This command starts tests with the number of workers equal to CPU cores.
The useful command to discover the tests in the file or directory is
pytest --collect-only -q --mode dev test/boost/aggregate_fcts_test.cc
That will return all test functions in the file.
To execute only one function from the test, you can invoke the output from the previous command.
However, suffix for mode should be skipped.
For example,
output shows in the terminal something like this test/boost/aggregate_fcts_test.cc::test_aggregate_avg.dev.
So to execute this specific test function, please use the next command
pytest --mode dev test/boost/aggregate_fcts_test.cc::test_aggregate_avg
Writing tests
Because of the large build time and build size of each separate test executable, it is recommended to put test functions into relatively large source files. But not too large - to keep compilation time of a single source file (during development) at reasonable levels.
When adding new source files in test/boost, don't forget to list the new source file in configure.py and also in CMakeLists.txt. The former is needed by our CI, but the latter is preferred by some developers.