Massive increase in MySQL load after upg from 8.2.3 to 8.2.5 #24651

Closed
scolebrook opened this Issue May 16, 2016 · 10 comments

Projects

None yet

6 participants

@scolebrook
Contributor

The function in this commit
#24000
resulted in a 1500% increase in mysql select traffic after our upgrade from 8.2.3 to 8.2.5.

We are using CentOS 6.7 with apache 2.2.15 on our web servers. Percona mysql galera cluster 5.6.28-76.1-56 with 3 nodes (also CentOS 6.7) and HAProxy 1.5.4 on CentOS 6.7 for failover. We have all traffic go to one node to avoid deadlocks.

After commenting out the function in this commit we saw traffic drop from ~15k queries/sec to 1000 queries/sec, almost entirely selects. But at times we'd seen select query loads as high as 45k/sec.

This function appears to cause some kind of looping for propfinds from the client during the discovery phase when processing shares. We turned logging of sql queries and saw the same shares looping over and over. Our user base is global so as time went on, users were going to bed and other users were starting work and so the names of the shares in the sql queries changed, but the pattern of looping remained.

@MorrisJobke
Member
@rullzer
Contributor
rullzer commented May 17, 2016

@icewind1991 didn't we find a workaround for 9.0 for this?

@PVince81 PVince81 added this to the 8.2.6-current-maintenance milestone May 17, 2016
@PVince81
Collaborator

@icewind1991 would also be good to check whether this performance regression affects 9.0+ or is a side-effect of older code in 8.2.x. Because if it's only 8.2.x then we might want to revert that fix, which seemed to be there mostly to fix image orientation issues.

@timm2k
timm2k commented May 25, 2016

I can confirm this issue. We've upgraded from 8.1.6 to 8.2.5 a few hours ago and see a massive increase of queries: https://cs.uol.de/index.php/s/cR3o0LfzH5ncKTu.

Env:
RHEL 7.2
nginx 1.10 + PHP 5.6.21
MySQL 5.6.29 (percona galera cluster)

@icewind1991
Member

I believe this is no longer a problem with master/9.1 with the reworking of the SharedStorage

Will look into a sollution for 8.2/9.0

@icewind1991
Member

9.0 fix is here #24839

I'll try to come up with a proper fix for 8.2 but it might be best to just revert the original isLocal fix

@rullzer
Contributor
rullzer commented May 31, 2016

This is fixed now I guess?

@timm2k
timm2k commented May 31, 2016

for me: yes. Amount of queries of ownCloud 8.2.5 reduces after I've applied this patch.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment