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After the merging of MDEV-24915, 10.6 branch has regressions with handling of concurrent write load against two or more cluster nodes. These regressions may surface as cluster hanging, node crashes or data inconsistency. With some test scenarios, the only visible symptom could be that the BF victim aborting happens only by innodb lock wait timeout expiration. This would result only to poor performance (by default 50 sec hang for each BF conflict), and could be somewhat difficult to diagnose. This pull request has following fixes to handle concurrent write load from multiple nodes: In lock_wait_wsrep_kill(), the victim trx was expected to be only in TRX_STATE_ACTIVE state. With the delayed BF conflict handling, it can happen that victim has advanced into pre commit state. This was fixed by choosing victim both in TRX_STATE_ACTIVE and TRX_STATE_PREPARED states. Victim transaction may be in several different states at the time of detected lock conflict, and due to delayed BF aborting practice in MDEV-24915, the victim may advance further before the actual BF aborting takes place. The BF aborting in MDEV-24915 did not wake the victim, if it was in the state of waiting for some other lock (than the one that was blocking the high priority thread). This anomaly caused the innodb lock wait timeout expiration delays and poor performance symptom. To fix this, lock_wait_wsrep_kill() now looks if victim is in lock waiting state, and uses lock_cancel_waiting_and_release() to cancel this lock wait. wsrep_bf_abort() checks if the victim has active transaction (in wsrep-lib), and starts a new transaction if there was no active transaction before. Due to late BF aborting, the victim may have e.g. failed in certification and is already aborting or has aborted at this stage. This has caused problems in testing where BF aborter tries to BF abort himself. The fix in wsrep_bf_abort() now skips the BF abort, if victim is aborting or has aborted. Victim may not have started transaction yet in wsrep context, but it may have acquired MDL locks (due to DDL execution), and this has caused BF conflict. Such case does not require aborting in wsrep or replication provider state. BF aborting could cause BF-BF conflict scenario, if victim was already aborted and changed to replayer having high priority as well. This BF-BF conflict scenario is now avoided in lock_wait_wsrep() where we now check if blocking lock holder is also high priority and is ordered before, caller should wait for the lock in this situation. The natural innodb deadlock resolving algorithm could pick BF thread as deadlock victim. This is fixed by giving max weigh to BF threads in Deadlock::report(). MDEV-24341 has changed excution paths in do_command() and this affects BF aborted victim execution. This PR fixes one assert in do_command(): DBUG_ASSERT(!thd->async_state.pending_ops()) Which fired if the thd was BF aborted earlier. This assert is now changed to allow pending_ops() if thd was BF aborted before. With these fixes, long term highly conflicting write load could be run against to node cluster. If binlogging is configured, log_slave_updates should be also set.
This directory contains test suites for the MariaDB server. To run currently existing test cases, execute ./mysql-test-run in this directory. Some tests are known to fail on some platforms or be otherwise unreliable. The file "unstable-tests" contains the list of such tests along with a comment for every test. To exclude them from the test run, execute # ./mysql-test-run --skip-test-list=unstable-tests In general you do not have to have to do "make install", and you can have a co-existing MariaDB installation, the tests will not conflict with it. To run the tests in a source directory, you must do "make" first. In Red Hat distributions, you should run the script as user "mysql". The user is created with nologin shell, so the best bet is something like # su - # cd /usr/share/mysql-test # su -s /bin/bash mysql -c "./mysql-test-run --skip-test-list=unstable-tests" This will use the installed MariaDB executables, but will run a private copy of the server process (using data files within /usr/share/mysql-test), so you need not start the mysqld service beforehand. You can omit --skip-test-list option if you want to check whether the listed failures occur for you. To clean up afterwards, remove the created "var" subdirectory, e.g. # su -s /bin/bash - mysql -c "rm -rf /usr/share/mysql-test/var" If one or more tests fail on your system on reasons other than listed in lists of unstable tests, please read the following manual section for instructions on how to report the problem: https://mariadb.com/kb/en/reporting-bugs If you want to use an already running MySQL server for specific tests, use the --extern option to mysql-test-run. Please note that in this mode, you are expected to provide names of the tests to run. For example, here is the command to run the "alias" and "analyze" tests with an external server: # mysql-test-run --extern socket=/tmp/mysql.sock alias analyze To match your setup, you might need to provide other relevant options. With no test names on the command line, mysql-test-run will attempt to execute the default set of tests, which will certainly fail, because many tests cannot run with an external server (they need to control the options with which the server is started, restart the server during execution, etc.) You can create your own test cases. To create a test case, create a new file in the main subdirectory using a text editor. The file should have a .test extension. For example: # xemacs t/test_case_name.test In the file, put a set of SQL statements that create some tables, load test data, and run some queries to manipulate it. Your test should begin by dropping the tables you are going to create and end by dropping them again. This ensures that you can run the test over and over again. If you are using mysqltest commands in your test case, you should create the result file as follows: # mysql-test-run --record test_case_name or # mysqltest --record < t/test_case_name.test If you only have a simple test case consisting of SQL statements and comments, you can create the result file in one of the following ways: # mysql-test-run --record test_case_name # mysql test < t/test_case_name.test > r/test_case_name.result # mysqltest --record --database test --result-file=r/test_case_name.result < t/test_case_name.test When this is done, take a look at r/test_case_name.result. If the result is incorrect, you have found a bug. In this case, you should edit the test result to the correct results so that we can verify that the bug is corrected in future releases. If you want to submit your test case you can send it to maria-developers@lists.launchpad.net or attach it to a bug report on https://mariadb.org/jira/. If the test case is really big or if it contains 'not public' data, then put your .test file and .result file(s) into a tar.gz archive, add a README that explains the problem, ftp the archive to ftp://ftp.askmonty.org/private and submit a report to https://mariadb.org/jira about it. The latest information about mysql-test-run can be found at: https://mariadb.com/kb/en/mariadb/mysqltest/ If you want to create .rdiff files, check https://mariadb.com/kb/en/mariadb/mysql-test-auxiliary-files/