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MEMORY LEAK. Background: - There are caches for stored functions and stored procedures (SP-cache); - There is no similar cache for events; - Triggers are cached together with TABLE objects; - Those SP-caches are per-session (i.e. specific to each session); - A stored routine is represented by a sp_head-instance internally; - SP-cache basically contains sp_head-objects of stored routines, which have been executed in a session; - sp_head-object is added into the SP-cache before the corresponding stored routine is executed; - SP-cache is flushed in the end of the session. The problem was that SP-cache might grow without any limit. Although this was not a pure memory leak (the SP-cache is flushed when session is closed), this is still a problem, because the user might take much memory by executing many stored routines. The patch fixes this problem in the least-intrusive way. A soft limit (similar to the size of table definition cache) is introduced. To represent such limit the new runtime configuration parameter 'stored_program_cache' is introduced. The value of this parameter is stored in the new global variable stored_program_cache_size that used to control the size of SP-cache to overflow. The parameter 'stored_program_cache' limits number of cached routines for each thread. It has the following min/default/max values given from support: min = 256, default = 256, max = 512 * 1024. Also it should be noted that this parameter limits the size of each cache (for stored procedures and for stored functions) separately. The SP-cache size is checked after top-level statement is parsed. If SP-cache size exceeds the limit specified by parameter 'stored_program_cache' then SP-cache is flushed and memory allocated for cache objects is freed. Such approach allows to flush cache safely when there are dependencies among stored routines. sql/mysqld.cc: Added global variable stored_program_cache_size to store value of configuration parameter 'stored-program-cache'. sql/mysqld.h: Added declaration of global variable stored_program_cache_size. sql/sp_cache.cc: Extended interface for sp_cache by adding helper routine sp_cache_enforce_limit to control size of stored routines cache for overflow. Also added method enforce_limit into class sp_cache that implements control of cache size for overflow. sql/sp_cache.h: Extended interface for sp_cache by adding standalone routine sp_cache_enforce_limit to control size of stored routines cache for overflow. sql/sql_parse.cc: Added flush of sp_cache after processing of next sql-statement received from a client. sql/sql_prepare.cc: Added flush of sp_cache after preparation/execution of next prepared sql-statement received from a client. sql/sys_vars.cc: Added support for configuration parameter stored-program-cache.
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