PcSx2 & AMD X4 CPU
#1
...OK, we all know that only two cores are usable by this emulator, well, I don't know if anyone else has noticed this, but this emu is working on full speed on my AMD Phenom II 955 BE CPU on stock speed aka 3.2GHz, & on my old AMD Athlon 64 6400+ X2 it could't run even 60%, now, I know this new core is much better then old one, but there is something else that I noticed, ...this emu is using all four cores of my cpu, when I turned off two cores it went around 80% of speed, when I turn them back, it goes 95-100% of speed ingame... Can someone explain me this, couse all the way it was said that this emu uses only two cores?
I use PCSX2 Beta 1474 & rig is in signature...

Cheers...
AMD FX-8350
4x 4GB DDR3 2400MHz
AMD Radeon R9 Fury X
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#2
When you set affinity do you use the first 2 (CPU0 and CPU1) or the last two? If it's the first two, it could be because the OS is trying to use the CPU at the same time. Try setting affinity for PCSX2 to the last 2 processors.
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#3
There is a known bug in Beta 1474 that causes affinity for the EEcore thread of PCSX2 to get locked to Core0 of your CPU. This causes performance degradation when you limit the number of cores the process has access too. Newer SVNs should fix it so that two core affinity performs roughly equal to 4 core affinity.
Jake Stine (Air) - Programmer - PCSX2 Dev Team
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#4
...well, I didn't do it through Windows, but through BIOS, there is a option to turn off cores, & yes, I try different combinations...

Sorry, didn't say game, it was Gran Turismo 4 that I was trying, ...well bug or not bug, I like it... that is how it is working right now xD

Cheers...
AMD FX-8350
4x 4GB DDR3 2400MHz
AMD Radeon R9 Fury X
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#5
(08-21-2009, 09:54 AM)rex1825 Wrote: ...well, I didn't do it through Windows, but through BIOS, there is a option to turn off cores, & yes, I try different combinations...

What you are talking about is activating/deactivating cores, while Koji was referring to the "Define affinity" settings that is available in the task manager, under the "processes" tab. It allows you to choose which programs use which cores.

To sum up, deactivating core 0 and core 1 isn't the same as telling PCSX2 to use core 2 and 3 only while leaving the two first ones for the OS.
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#6
Yeah turning off two cores in your BIOS could very well have adverse effects on the performance of just about everything on your system, regardless of how many threads they use. Though I still suspect the reason for the bulk of the penalty in PCSX2 is because of that affinity bug -- it caused ~25% speed loss on dual core AMDs. But I'd still expect like 5-10% speed loss in general from disabling 2 cores in your BIOS.
Jake Stine (Air) - Programmer - PCSX2 Dev Team
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#7
...ok now, I did what you said before, but I see again less performance when I set affinity to 2 & 3 core so the 0 & 1 stay free, so I'd say that it uses all cores for what ever it uses, couse system (aka Windows XP in my case) is using 5% max of CPU resources (& only first - 0 core) when doing nothing, all other goes to PcSx2...

& as I said, GT4 is working much better now, 95-100%... so It's good to me xD

Cheers...
AMD FX-8350
4x 4GB DDR3 2400MHz
AMD Radeon R9 Fury X
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#8
(08-23-2009, 05:11 PM)rex1825 Wrote: ...ok now, I did what you said before, but I see again less performance when I set affinity to 2 & 3 core so the 0 & 1 stay free, so I'd say that it uses all cores for what ever it uses, couse system (aka Windows XP in my case) is using 5% max of CPU resources (& only first - 0 core) when doing nothing, all other goes to PcSx2...

& as I said, GT4 is working much better now, 95-100%... so It's good to me xD

Cheers...


What windows you are using? Windows 7 RTM?
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#9
...Windows XP SP3 32bit version...

Cheers...
AMD FX-8350
4x 4GB DDR3 2400MHz
AMD Radeon R9 Fury X
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#10
I thought, that Phenom II decrease cache size when you turn out cores, so it's just normal that game speed would be degrade on 2-cores mode instead 4.
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