Hi Lech,
Thanks for submitting the patch to SchedMD:
https://bugs.schedmd.com/show_bug.cgi?id=6796
SchedMD already decided that they won't fix the problem:
Thank you for the submission, but I will not be merging this upstream at this
time.
Support for the 17.11 release is nearly ended, and we do not expect to make any
further maintenance releases on that branch.
For 18.08, we're rather late in to the lifecycle to make a change this
significant to the MySQL conversion code, and I will not be passing this along
in to our review process for further evaluation. Our recommendation to sites to
run a modern MySQL/MariaDB version stands as our primary means of avoiding this
class of issues.
Can you confirm that your patch is only relevant for an old MySQL 5.1?
On our CentOS 7 systems we run the OS's MariaDB server 5.5. Would
MySQL/MariaDB version 5.5 be affected by your patch or not?
Best regards,
Ole
On 4/3/19 12:30 PM, Lech Nieroda wrote:
Hello Chris,
I’ve submitted the bug report together with a patch.
We don’t have a support contract but I suppose they’ll at least read it ;)
The code is identical for 18.08.x and 19.05.x, it’s just a different offset.
Kind regards,
Lech
Am 02.04.2019 um 15:18 schrieb Ole Holm Nielsen <ole.h.niel...@fysik.dtu.dk>:
Hi Lech,
IMHO, the Slurm user community would benefit the most from your interesting
work on MySQL/MariaDB performance, if
https://bugs.schedmd.com/show_bug.cgi?id=6796your patch could be made against
the current 18.08 and the coming 19.05 releases. This would ensure that your
work is carried forward.
Would you be able to make patches against 18.08 and 19.05? If you submit the
patches to SchedMD, my guess is that they'd be very interested. A site with a
SchedMD support contract (such as our site) could also submit a bug report
including your patch.
/Ole
On 4/2/19 2:56 PM, Lech Nieroda wrote:
That’s probably it.
Sub-queries are known for potential performance issues, so one wonders why the
devs didn’t extract it accordingly and made the code more robust or at least
compatible with RHEL/CentOS 6 rather than including that remark in the release
notes.
Am 02.04.2019 um 07:20 schrieb Chris Samuel <ch...@csamuel.org>:
On Monday, 1 April 2019 7:55:09 AM PDT Lech Nieroda wrote:
Further analysis of the query has shown that the mysql optimizer has choosen
the wrong execution plan. This may depend on the mysql version, ours was
5.1.69.
I suspect this is the issue documented in the release notes for 17.11:
https://github.com/SchedMD/slurm/blob/slurm-17.11/RELEASE_NOTES
NOTE FOR THOSE UPGRADING SLURMDBD: The database conversion process from
SlurmDBD 16.05 or 17.02 may not work properly with MySQL 5.1 (as was the
default version for RHEL 6). Upgrading to a newer version of MariaDB or
MySQL is strongly encouraged to prevent this problem.
