96a3544739
Before this series, Alternator's Query and Scan operations convert an entire result page to JSON without yielding. For a page of maximum size (1MB) and tiny rows, this can cause a significant stall - the test included in this PR reported stalls of 14-26ms on my laptop. The problem is the describe_items() function, which does this conversion immediately, without yielding. This patch changes this function to return a future, and use a new result_set::visit_gently() method that does what visit() does, but with yields when needed. This PR improves #17995, but does not completely fix is as the stalls in the are not completely eliminated. But on my laptop it usually reduces the stalls to around 5ms. It appears that the remaining stalls some from other places not fixed in this PR, such as perhaps query_page::handle_result(), and will need to be fixed by additional patches. Closes scylladb/scylladb#18036 * github.com:scylladb/scylladb: alternator: reduce stall for Query and Scan with large pages result_set: introduce visit_gently() alternator: coroutinize do_query() function
Scylla in-source tests.
For details on how to run the tests, see docs/dev/testing.md
Shared C++ utils, libraries are in lib/, for Python - pylib/
alternator - Python tests which connect to a single server and use the DynamoDB API unit, boost, raft - unit tests in C++ cql-pytest - Python tests which connect to a single server and use CQL topology* - tests that set up clusters and add/remove nodes cql - approval tests that use CQL and pre-recorded output rest_api - tests for Scylla REST API Port 9000 scylla-gdb - tests for scylla-gdb.py helper script nodetool - tests for C++ implementation of nodetool
If you can use an existing folder, consider adding your test to it. New folders should be used for new large categories/subsystems, or when the test environment is significantly different from some existing suite, e.g. you plan to start scylladb with different configuration, and you intend to add many tests and would like them to reuse an existing Scylla cluster (clusters can be reused for tests within the same folder).
To add a new folder, create a new directory, and then
copy & edit its suite.ini.