0d35c96ef4
Fixes #16298 The adjusted buffer position calculation in buffer_position(), introduced in #15494 was in fact broken. It calculated (like previously) a "position" based on diff between underlying buffer size and ostream size() (i.e. avail), then adjusted this according to sector overhead rules. However, the underlying buffer size is in unadjusted terms, and the ostream is adjusted. The two cannot be compared as such, which means the "positions" we get here are borked. Luckily for us (sarcasm), the position calculation in replayer made a similar error, in that it adjusts up current position by one sector overhead to much, leading to us more or less getting the same, erroneous results in both ends. However, when/iff one needs to adjust the segment file format further, one might very quickly realize that this does not work well if, say, one needs to be able to safely read some extra bytes before first chunk in a segment. Conversely, trying to adjust this also exposes a latent potential error in the skip mechanism, manifesting here. Issue fixed by keeping track of the initial ostream capacity for segment buffer, and use this for position calculation, and in the case of replayer, move file pos adjustment from read_data() to subroutine (shared with skipping), that better takes data stream position vs. file position adjustment. In implementaion terms, we first inc the "data stream" pos (i.e. pos in data without overhead), then adjust for overhead. Also fix replayer::skip, so that we handle the buffer/pos relation correctly now. Added test for intial entry position, as well as data replay consistency for single entry_writer paths.
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.