[mythtv-users] High mysql cpu usage

[Michael T. Dean]

On 12/30/2012 12:25 PM, Jarle Thorsen wrote:
> 2012/12/30 David Scammell
>
>> At the end of the day I'm unsure if there's a problem with indexes but
>> my situation was fixed by setting the visible=0 setting on a number of
>> 'useless' channels that i'm unlikely to record from, bringing the
>> number of visible channels to about 90. My longest slow query is now
>> 13 seconds, once or twice a day.
>>
> I have currently about 700 channels, and I am in the process of deleting
> channels that I can not tune in to. I'm thinking that my number of
> (possibly) bad channels may contribute to my problem.
>
> I have seen some reports of similar problems for ext4 users, but I'm not
> running ext4 on my box.

It's not just ext4.  It's most any file system with barriers 
enabled--because that slows write speeds to platter write speeds (it 
completely disables disk cache (in software /and/ hardware) for writes).

Mike