[mythtv-users] HD 1080i Jerky playback while recording
Steve Malenfant
smalenfant at gmail.com
Fri Jan 6 04:02:32 UTC 2006
Scenario :
- Backend recording NBC in HD 1080i
- Frontend playing the NBC show in 1080i
Result : Jerky playback
As soon as the show finish recording, the playback is fine. If I do
the same on a recording in 720p, it doesn't happen.
The only I could see is that the CPU is used at 45% and the "wa" state
uses the rest (0-1 % idle).
Usage when recording on backend and watching on frontend :
top - 22:58:38 up 4:21, 4 users, load average: 1.90, 1.19, 1.13
Tasks: 117 total, 1 running, 115 sleeping, 0 stopped, 1 zombie
Cpu(s): 41.7% us, 3.3% sy, 0.0% ni, 0.3% id, 51.3% wa, 3.3% hi, 0.0% si
Mem: 1035872k total, 936812k used, 99060k free, 6528k buffers
Swap: 690752k total, 708k used, 690044k free, 579356k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
6293 root 15 0 379m 147m 19m S 42.3 14.6 1:19.09 mythfrontend
3026 root 15 0 194m 60m 7720 S 1.7 6.0 3:09.03 X
Usage when not recording and watching the same show :
top - 23:01:19 up 4:24, 4 users, load average: 2.40, 1.76, 1.35
Tasks: 117 total, 3 running, 113 sleeping, 0 stopped, 1 zombie
Cpu(s): 43.2% us, 0.7% sy, 0.0% ni, 55.1% id, 0.3% wa, 0.7% hi, 0.0% si
Mem: 1035872k total, 936116k used, 99756k free, 6788k buffers
Swap: 690752k total, 708k used, 690044k free, 576456k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
6293 root 15 0 382m 149m 19m S 42.0 14.8 2:59.47 mythfrontend
3026 root 15 0 194m 60m 7720 S 0.7 6.0 3:19.36 X
Any ideas why the "wa" is using so much of the CPU time only when the
backend is recording?
wa: Time spent waiting for IO. Prior to Linux 2.5.41, shown as zero.
Steve M.
More information about the mythtv-users
mailing list