TUSA/TX-Gunslinger
05-02-2011, 04:25 AM
I've done a lot of controlled "The Black Death" track replays, and since it's Monday in Russia - I thought I'd post my findings.
Here are graphs of 6 successive track playbacks attempting to isolate the cause of random stuttering and pausing on some track playbacks but not others. The following two examples iterate ProcessingAffinityMask and show the performance of CPU/GPU syncronized with other measurements and Fraps results.
All my settings and system configuration is listed on these first two examples which display 22 minutes of data overall - each TBD track is 3 mins 40 secs in duration:
Note: My HD5870 GPU is operating at maximum clock during loading from CoD track playback
https://webspace.utexas.edu/joem/CLIFFS%20OF%20DOVER/1.00.4305%20testing/Sat-6-ProcAffinity%3D15-runs-including%20load%20FINAL.jpg
https://webspace.utexas.edu/joem/CLIFFS%20OF%20DOVER/1.00.4305%20testing/Sat-6-ProcAffinity%3DOFF-runs-including%20load%20FINAL.jpg
Note the playbacks in which the fps was 0 or lower than 10. Those are track playbacks with significant pausing and stuttering.
Now here's a couple sets of measurements over two different tracks - at higher time resolution so you can see the relationship between GPU and CPU loading during a stutter/pause and a track with good performance - i.e. no stutter or pausing
First the smooth track playback, note that GPU loading (purple) never drops lower than 50% during the track.
https://webspace.utexas.edu/joem/CLIFFS%20OF%20DOVER/1.00.4305%20testing/Anatomy%20of%20a%20Stutter%20-%20exm%201%20good%20performance.jpg
Now a playback which had significant pause (like 2 seconds). Note that during the stutter the CPU (yellow) drops to 0 first - then the GPU (purple) drops to 0.
https://webspace.utexas.edu/joem/CLIFFS%20OF%20DOVER/1.00.4305%20testing/Anatomy%20of%20a%20Stutter%20-%20exm%202%20bad%20performance.jpg
No matter what Catalyst setting or CoD setting I changed - the stuttering and pausing continued randomly throughout testing. Many times, I thought one setting or the other had improved it - but follow on testing produced more stutter tracks.
In summary - It's the CPU not the GPU that producing the stutter and pausing.
As has been reported many times - the AA only works in two modes - OFF and 1X-2X-4X-8X all producing the same graphic output. Strangley, I found performance better at higher settings even though the screen output was the same.
https://webspace.utexas.edu/joem/CLIFFS%20OF%20DOVER/1.00.4305%20testing/1.00.4305-AAsettingsVsActual.jpg
S!
Gunny
Here are graphs of 6 successive track playbacks attempting to isolate the cause of random stuttering and pausing on some track playbacks but not others. The following two examples iterate ProcessingAffinityMask and show the performance of CPU/GPU syncronized with other measurements and Fraps results.
All my settings and system configuration is listed on these first two examples which display 22 minutes of data overall - each TBD track is 3 mins 40 secs in duration:
Note: My HD5870 GPU is operating at maximum clock during loading from CoD track playback
https://webspace.utexas.edu/joem/CLIFFS%20OF%20DOVER/1.00.4305%20testing/Sat-6-ProcAffinity%3D15-runs-including%20load%20FINAL.jpg
https://webspace.utexas.edu/joem/CLIFFS%20OF%20DOVER/1.00.4305%20testing/Sat-6-ProcAffinity%3DOFF-runs-including%20load%20FINAL.jpg
Note the playbacks in which the fps was 0 or lower than 10. Those are track playbacks with significant pausing and stuttering.
Now here's a couple sets of measurements over two different tracks - at higher time resolution so you can see the relationship between GPU and CPU loading during a stutter/pause and a track with good performance - i.e. no stutter or pausing
First the smooth track playback, note that GPU loading (purple) never drops lower than 50% during the track.
https://webspace.utexas.edu/joem/CLIFFS%20OF%20DOVER/1.00.4305%20testing/Anatomy%20of%20a%20Stutter%20-%20exm%201%20good%20performance.jpg
Now a playback which had significant pause (like 2 seconds). Note that during the stutter the CPU (yellow) drops to 0 first - then the GPU (purple) drops to 0.
https://webspace.utexas.edu/joem/CLIFFS%20OF%20DOVER/1.00.4305%20testing/Anatomy%20of%20a%20Stutter%20-%20exm%202%20bad%20performance.jpg
No matter what Catalyst setting or CoD setting I changed - the stuttering and pausing continued randomly throughout testing. Many times, I thought one setting or the other had improved it - but follow on testing produced more stutter tracks.
In summary - It's the CPU not the GPU that producing the stutter and pausing.
As has been reported many times - the AA only works in two modes - OFF and 1X-2X-4X-8X all producing the same graphic output. Strangley, I found performance better at higher settings even though the screen output was the same.
https://webspace.utexas.edu/joem/CLIFFS%20OF%20DOVER/1.00.4305%20testing/1.00.4305-AAsettingsVsActual.jpg
S!
Gunny