The log for changes during the online ALTER goes in the tmp dir. The log is applied at the end of the statement.
Sent from my iPhone > On May 4, 2016, at 2:13 AM, Sergei Golubchik <s...@mariadb.org> wrote: > > Hi, Rhys.Campbell! > >> On May 04, rhys.campb...@swisscom.com wrote: >> Hi All, >> >> For the following statement... >> >> ALTER ONLINE TABLE dom_audit_event ENGINE=INNODB, ALGORITHM=INPLACE; >> >> I can still see that MariaDB is still using the value of tmpdir. We >> have this set to tmpfs on some of our servers and this causes some >> ALTER statements on big tables to fail. It was my understanding that >> if you specified INPLACE then the statement would fail if this was not >> possible. > > Yes, your understanding is correct. > > Furthermore, copy (not inplace) ALTER does not use tmpdir, it creates a > temporary table in the datadir, and later renames it to the actual table > name. If the temporary table were created in tmpdir, it could not be > renamed to a different filesystem. > > So, that tmpdir usage you're seeing is not due to not-inplace alter. > The alter isstill done inplace, and tmpdir is used for something else. > Probaby for merge sort. > > Regards, > Sergei > Chief Architect MariaDB > and secur...@mariadb.org > > _______________________________________________ > Mailing list: https://launchpad.net/~maria-discuss > Post to : maria-discuss@lists.launchpad.net > Unsubscribe : https://launchpad.net/~maria-discuss > More help : https://help.launchpad.net/ListHelp _______________________________________________ Mailing list: https://launchpad.net/~maria-discuss Post to : maria-discuss@lists.launchpad.net Unsubscribe : https://launchpad.net/~maria-discuss More help : https://help.launchpad.net/ListHelp
