Bug #85331 | _characterset specifications have lousy performance for some character sets | ||
---|---|---|---|
Submitted: | 6 Mar 2017 19:46 | Modified: | 27 Sep 2017 2:00 |
Reporter: | Domas Mituzas | Email Updates: | |
Status: | Closed | Impact on me: | |
Category: | MySQL Server: Charsets | Severity: | S3 (Non-critical) |
Version: | 5.6, 5.7, etc, 5.6.35 | OS: | Any |
Assigned to: | CPU Architecture: | Any |
[6 Mar 2017 19:46]
Domas Mituzas
[7 Mar 2017 8:38]
MySQL Verification Team
Verified on my non-scientific single-threaded tests on windows 5.7.17. I got: 63K qps for query: select _big5''; 58K qps for query: select _cp932; big5 is at the start of the list and _cp932 near the end of the list. Will let Umesh verify under perf/mysqlslap on linux..
[7 Mar 2017 12:10]
MySQL Verification Team
Hello Domas, Thank you for the report. Thanks, Umesh
[7 Mar 2017 12:12]
MySQL Verification Team
Thank you Shane for quickly verifying and helping me on rest things on this :)
[27 Sep 2017 2:00]
Paul DuBois
Posted by developer: Fixed in 9.0.0. For constructs using _charset character set introducers (for example, _utf8mb4 'abc'), lookup performance was improved for mapping the introducer onto the proper character set.