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Recently, the playground version improved MTGS mode (runs faster with some games. not really noticable when compared to the official version due to the various changes in speed between the two). DC mode was then removed as it wasn't very useful and was just causing 100% cpu usage for no gain.
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I don't understand what exactly you're trying to ask / say but this thread belongs to the Playground forum,moving!
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12-13-2008, 05:48 AM
(This post was last modified: 12-13-2008, 05:50 AM by Air.)
(12-13-2008, 01:21 AM)tallbender Wrote: Is PG versions is based on DC mode? since that one is no longer be selected....when i analysed playing Legaia 2
uel Saga my cpu usage was:
PG:as high as 98%
PP396-REV367:as high as 86%
*No changes on FPS on both versions still good speed.
*mostly my previous versions in the cpu config i only enable MTGS mode.
DC mode is obsolete, and was never very good anyway. Some games ran faster with DC checked, others ran same speed or slower. Yes, CPU usage was higher, but then again I could make CPU usage very high by pasting this into Pcsx2:
Code:
for( int i=0; i<100000; i++ ) doNothing();
That would give you 98% CPU but I don't think you'd be happy with the result.
The reason CPU usage does not get to 100% anymore is because one of your cores is waiting for the other to catch up, and in waiting it does not register CPU usage. On some games, the GPU thread must wait for the EmotionEngine thread to send it information. On other games, the EmotionEngine thread must wait for the GPU to finish rendering the current scene. Which thread is waiting for the other depends on the game and your hardware (CPU/GPU speeds). The old DC mode basically did a busy wait similar to the code snippet above whenever one thread/core was waiting for the other to catch up. I replaced it with a proper set of mutex waits/locks, which sped things up by 2-4% on both DualCore machines and SingleCore Hyperthreaded machines -- thus no more DC mode checkbox needed.
Jake Stine (Air) - Programmer - PCSX2 Dev Team
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-100 % cpu usege on dc mode? could harm the cpu any way?
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