Re: [Maria-developers] 9243921c84b: Make all #sql temporary table names uniform

Hi, Michael! On Apr 13, Michael Widenius wrote:

revision-id: 9243921c84b (mariadb-10.5.2-128-g9243921c84b) parent(s): 8742d176bc2 author: Michael Widenius committer: Michael Widenius timestamp: 2020-04-09 22:02:06 +0300 message:

Make all #sql temporary table names uniform

The reason for this is to make all temporary file names similar and also to be able to figure out from where a #sql-xxx name orginates.

New format is for most cases: #sql-name-current_pid-thread_id[-increment] Where name is one of subselect, alter, exchange, temptable or backup

The execptions are:

typo, "exceptions"

ALTER PARTITION shadow files: #sql-shadow-'original_table_name'

Please, add a thread_id here at the end. normally MDL should ensure that no two threads can have a shadow for the same table at the same time, but we have enough bugs as it is to introduce another vector when two threads can overwrite each other temp files.

Names from the temp pool: #sql-name-current_pid-pool_number

Would you mind if I drop temp pool completely in 10.5? It was added by Jeremy in January 2001 with the comment Added --temp-pool option to mysqld. This will cause temporary files created to use a small set of filenames, to try and avoid problems in the Linux kernel. And I doubt it's still an issue in 2020. Regards, Sergei VP of MariaDB Server Engineering and security@mariadb.org