[mythtv-users] How high is cpu usage supposed to be?

[Ray Olszewski]

At 12:38 PM 7/11/2003 -0700, Taylor Dondich wrote:
>I'm running everything on one machine.  When I start playing livetv, cpu 
>usage goes to 93% user, approx 5.0% system.  The mythbackend is taking up 
>70% of cpu and mythfrontend takes up about 30%.  I'm wondering if this is 
>abnormal, because sometimes, after a period of livetv playback, the system 
>freezes up.  I'm now monitoring it from a window to see what happens, but 
>I'd like to know if anyone has any input.


As posed, this is a meaningless question. Whether CPU usage is "abnormal" 
is not independent of --

         1. Type and speed of CPU. What you report would be very hight for 
a fast P4 but impressively low for a 533 MHz Celeron.

         2. Type of vidcap card. Cards with hardware encoding use way less 
CPU than (say) bttv cards.

         3. Encoding settings. MPEG4 uses more CPU than RTJPEG. More 
capture resolution and/or greater bps settings use more CPU. I'd imagine 
(never tested this) that NTSC (29.97 fps) uses more CPU than PAL (25 fps).

Possible causes of abnormally high CPU use are an X driver that does not 
(either properly or at all)  support XVideo, failure to use DMA on hard 
drives, and noisy source signal. But it is impossible to say whether your 
CPU usage is abnormal or not.