[mythtv-users] Mythfrontend idle cpu consumption help

[Nick Rout]

On Wed, Jan 27, 2010 at 7:13 AM, jansenj <jansenj+myth at gmail.com> wrote:
>
>> Would it be possible for you to try out the patch in ticket #7953?  I
>> know that QTimer should be responsible for up to 1ms of spin-waiting
>> per signal, but you (and everyone else in the 14-15% camp) are
>> spending 2ms of CPU time per signal.  I'd like to know if your idle
>> frontend CPU usage drops all the way to 1-2%, or only goes down to
>> 7-9%.
>
> The patch got mythfrontend down to spending most of the time at 0.7% usage,
> sometimes up to 1.3% while sitting idle on the main menu screen.
>
> If I read your patch correctly, you are just sleeping for a time equivalent
> to one period.  Its important to note that this makes your "real" animation
> pulse closer to 69Hz or so.  I don't know what was magical about 70Hz to
> begin with other than to have it be a faster sample rate than most screen
> refreshes.
>
> As some have said, the next step would be to connect it up to the screen
> refresh, or opengl vsync.  But your patch is a very good start, and would
> contend that something similar could be incorporated into the 0.22-fixes
> branch.  A guy can wish can't he?
>

I picked up from mythbuntu forums that setting TZ helps here. The poster stated:

"I think I found the solution to this. The problem was that the TZ
environment variable was not set and caused mythfrontend.real to spin
on trying to read /etc/localtime.

Once I set TZ, it was fine.

i.e.

export TZ=Canada/Toronto"

http://ubuntuforums.org/showthread.php?t=1293019

TZ isn't set on any of my boxes, but I am not running 0.22 to test.