[mythtv-users] High mysql cpu usage

[Jarle Thorsen]

2013/1/8 Michael T. Dean <mtdean at thirdcontact.com>

> You probably are using ext3 with barriers.  Please check:
>
> cat /proc/mounts
>
> and if you don't see "barrier=0", you're using barriers.
>

I was in fact using barriers. I edited my fstab:
UUID=f1f1cbe3-ef25-4dd5-b3ed-35deca2eeb37 / ext3
barrier=0,noatime,errors=remount-ro 0 1

I remounted and /proc/mounts says:
  /dev/disk/by-uuid/f1f1cbe3-ef25-4dd5-b3ed-35deca2eeb37 / ext3
rw,noatime,errors=remount-ro,data=ordered 0 0

(I don't think /proc/mounts is supposed to say barrier=0, but rather
data=ordered?)

However it only helped av very small amount. mysqld still uses 100% CPU
while "Reschedule requested for MATCH 0 0 0 - EITScanner", but now "only"
for 80 seconds compared to the earlier 90-100 seconds.


> I'm also guessing you're using the unsupported InnoDB storage engine.
>  InnoDB usage requires very specific configuration to get acceptable
> performance.
>

All my tables (except weather*) uses MyISAM so this does not seem to be
where the problem is hiding.

Other suggestions?


-- 
Jarle Thorsen
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