Hi, Ian! On Nov 05, Ian Gilfillan wrote: > I would like to document the Opened_plugin_libraries status variable, > introduced in MariaDB 10.0, but can't understand what it's all about. > > I have looked at: > http://lists.askmonty.org/pipermail/commits/2013-April/004595.html > but it's not really making sense what it's testing.
This is a merge changeset, it's not very helpful. Here's the one, that introduced the variable: http://bazaar.launchpad.net/~maria-captains/maria/10.0/revision/[email protected] The changeset comment says "... and a new status variable to cound successful dlopen's". So, Opened_plugin_libraries is incremented every time a shared library is opened. > In my own setup, each time I query the INFORMATION_SCHEMA.ALL_PLUGINS > table, Opened_plugin_libraries increments by 19 (no matter what > conditions I apply). Try to query INFORMATION_SCHEMA.ALL_PLUGINS for a specific library, like in the show_all_plugins.test from the changeset above: select * from information_schema.all_plugins where plugin_library='ha_example.so'; or show plugins soname 'ha_example.so'; In both these queries, MariaDB knows exactly that you're interested in ha_example.so, so it only opens that specific shared library. And Opened_plugin_libraries is incremented by 1. If you try (again, from the test file): show plugins soname like '%example%'; it will open all .so files that have "example" in their names, in the test suite it'll be dialog_examples.so, libdaemon_example.so, ha_example.so, udf_example.so. So, Opened_plugin_libraries will be incremented by 4. Note, that udf_example.so has no plugins inside, but MariaDB can only know that after opening the file. So it'll count in Opened_plugin_libraries, but it won't show up in the SHOW PLUGINS output. Otherwise, MariaDB will have to open all .so files in the plugin_dir, and apparently you happen to have 19 of them. Regards, Sergei _______________________________________________ Mailing list: https://launchpad.net/~maria-developers Post to : [email protected] Unsubscribe : https://launchpad.net/~maria-developers More help : https://help.launchpad.net/ListHelp
