[mythtv-users] Mythfilldatabase during recording screws up recordings.

[Alex Butcher]

On Mon, 4 Apr 2011, Douglas Peale wrote:

> On 04/04/2011 03:01 PM, Alex Butcher wrote:
>> On Mon, 4 Apr 2011, Douglas Peale wrote:
>>> On 04/04/2011 01:48 PM, Alex Butcher wrote:
>>>> On Sun, 3 Apr 2011, Douglas Peale wrote:
>>>>
>>>>> Is there any way to prevent mythfilldatabase from running simultaneous to a recording? Can something be done in the scheduler to
>>>>> keep them separate?
>>>> Why not use ionice?
> Thanks. I'm using Ubuntu though so I will have to do some improvising. It
> is unlikely I'll be able to use your changes directly.

Certainly.

> I think the most important is to get mysql running at idle IO class.  As
> far as I can tell,
> -c 2 -n 0 is the default for processes.

Hmm, I'm wary of only giving mysqld idle IO priority, in case it gets
starved, which in turn deadlocks mythbackend and friends. All I've done is
give mythfrontend and backend best effort IO with highest priority, and give
mysqld the same but one notch lower priority. Only long-lived batch
processes (mythcommflag-wrapper and MythArchive) are deprioritised to idle
(apart from the actual DVD burning bit!)

There's some scope for giving mythfrontend realtime priority, but again, I
fear it starving mythbackend or mysqld and causing a deadlock. My system
copes perfectly as it is, so I've felt no need to tinker further.

Best Regards,
Alex