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BUG#64503: mysql frequently ignores --relay-log-space-limit When the SQL thread goes to sleep, waiting for more events, it sets the flag ignore_log_space_limit to true. This gives the IO thread a chance to queue some more events and ultimately the SQL thread will be able to purge the log once it is rotated. By then the SQL thread resets the ignore_log_space_limit to false. However, between the time the SQL thread has set the ignore flag and the time it resets it, the IO thread will be queuing events in the relay log, possibly going way over the limit. This patch makes the IO and SQL thread to synchronize when they reach the space limit and only ask for one event at a time. Thus the SQL thread sets ignore_log_space_limit flag and the IO thread resets it to false everytime it processes one more event. In addition, everytime the SQL thread processes the next event, and the limit has been reached, it checks if the IO thread should rotate. If it should, it instructs the IO thread to rotate, giving the SQL thread a chance to purge the logs (freeing space). Finally, this patch removes the resetting of the ignore_log_space_limit flag from purge_first_log, because this is now reset by the IO thread every time it processes the next event when the limit has been reached. If the SQL thread is in a transaction, it cannot purge so, there is no point in asking the IO thread to rotate. The only thing it can do is to ask for more events until the transaction is over (then it can ask the IO to rotate and purge the log right away). Otherwise, there would be a deadlock (SQL would not be able to purge and IO thread would not be able to queue events so that the SQL would finish the transaction).
This directory contains a test suite for the MySQL daemon. To run the currently existing test cases, simply execute ./mysql-test-run in this directory. It will fire up the newly built mysqld and test it. Note that you do not have to have to do "make install", and you could actually have a co-existing MySQL installation. The tests will not conflict with it. All tests must pass. If one or more of them fail on your system, please read the following manual section for instructions on how to report the problem: http://dev.mysql.com/doc/mysql/en/mysql-test-suite.html 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, the test suite expects you to provide the 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 alias analyze To match your setup, you might also need to provide --socket, --user, and other relevant options. With no test cases named on the command line, mysql-test-run falls back to the normal "non-extern" behavior. The reason for this is that some tests cannot run with an external server. You can create your own test cases. To create a test case, create a new file in the t 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. We would appreciate it if you name your test tables t1, t2, t3 ... (to not conflict too much with existing tables). 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 (like result file names) 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 cases consisting of SQL statements and comments, you can create the test case 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 --record-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. To submit your test case, 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://support.mysql.com/pub/mysql/secret/ and send a mail to bugs@lists.mysql.com