pcsx and vista ram allocation problem

techniqu · May 18th, 2008, 23:19

for some reason vista is STILL caching all of my ram (all 8gb, more than enough for vista without caching) even though superfetch is turned off. even so, it does unload ram to load up programs, but it doesn't seem to work for pcsx2. does anyone know a fix for this or a fix for this problem in vista?

echosierra · May 19th, 2008, 00:17

This issue is not as simple as you may think. Do a search, there are numerous potential causes.

Do you have real-time antivirus and/or software firewall? Several are known to cause problems

techniqu · May 19th, 2008, 05:13

i'm pretty sure its ram because it tells me it's unable to allocate ram, and when I check my ram 100% of it is cached/in use. this only occurs when all my ram is allocated 100% as well, and I have no virus scan programs etc activated.

is there any way to stop vista from caching to my ram? i have superfetch turned off but it still keeps caching onto my ram using all of it after a while.

echosierra · May 19th, 2008, 06:00

PCSX2's memory allocation can fail even with RAM is available, which is why it's hard to figure out what exactly is causing it to fail.
The VM version of pcsx2 (the exe that doesn't have a 't') attempts to lock a very specific range of memory, and if for any reason it cannot you receive the memory allocation failure message.
Some antivirus and firewall software are known to inhabit the range that pcsx2 wants and won't give it up, even when they are not actually scanning anything. Do you have any antivirus or firewall software at all?

I'd also like you to clarify something for me.
Go to the Control Panel and open up the 'System' menu, under Computer it lists your processor then the amount of physical RAM present in the system. If this number isn't 8.00 then you don't actually have 8Gb of ram, Windows only provides the illusion that you do.
I'm curios because I can't think of a way to even use that much, much less do it without severely reducing the functionality of the computer.

techniqu · May 19th, 2008, 10:01

yeah I tested this with all forms of protection off. pcsx2 works and absolutely only fails to allocate (currently) when all my ram is cached. it is a physical 8gb; i built this computer myself and it recognizes it as 8. the problem is that in windows vista constantly caches things I'm not using and leaves no ram for pcsx2 to allocate. this doesn't cause system slowdown because its part of vista and vista normally unloads cache when you demand ram, but pcsx2 seems to allocate ram differently on startup and vista doesn't detect it or something so it just keeps my ram cached. the problem isn't system slowdown, its just that pcsx2 won't even start because of this allocation problem. this problem only occurs when I give vista enough time to cache all my ram though, otherwise i can use pcsx2 just fine.

nohea · May 19th, 2008, 10:43

Um, hi guys, do not wish to hijack the thread, but i started having this same problem myself just about fifteen minutes ago so i thought i'd add my two cents as well. (And yeah, I'm new here on the forum, but not really so with pcsx2 itself.) So um, i have vista too, x64 at it, with "only" have 4gb ram, but still, so far i've been able to run pcsx2 with no problem at all, even after i started up msn and browser too... now however, all i get is this failed to allocate enough memory message, right after a fresh new power-on, even tho i basically have no program whatsoever that'd be starting up automatically with windows, except for network of course and norton 360. and yet i'm getting this message thrown in my face. which is odd tho, because v0.9.2 starts up fine at the same time; unlike 0.9.4 (or even svn351, just thought i'd mention it). so the thing is, i did no changes in system settings whatsoever and yet the program fails...um, i can't help wondering: why exactly is a specific memory range required by pcsx2 even if there's plenty of ram available, could someone enlighten me please? i'm just curious.

Zal · May 19th, 2008, 19:54

Vista uses a good bit of ram just with the base OS. It likes to randomly lock the range of memory pcsx2 requires, pretty much after the system is booted in my experience you won't get that range back. If you restart the system that range of memory may be freed... although it might not heh...

__________________

echosierra · May 19th, 2008, 21:09

Pcsx2 grabs 0x35000000-0x55000000, or something close to that. It just so happens that several antivirus and firewall software programs like to place themselves inside this range, and they don't like giving it up.
The difference between the VM and the TLB version (the exe with 't') is that the VM version requires this very specific range, whereas the TLB doesn't. Not having this range means that each and every read/write to memory must be run through the translation-lookaside-buffer (TLB, get it?) to find out the physical location in RAM. The TLB translation takes time, and not having to do it is what makes the VM version faster.

Even when the antivirus or firewall software isn't actively scanning or doing anything, it can still inhabit this memory range. If updating/uninstalling the offending software doesn't fix it, you may just have to stick with the TLB version.

Last edited by echosierra; May 19th, 2008 at 21:15..

techniqu · May 20th, 2008, 01:32

echo, as i said before pcsx2 works for the hours leading up to full ram allocation through cache. ive tested it around 3 hours after boot where I still had about 1gb of uncached ram and it allocated just fine and ran disgaea 2 perfectly at impressive framerates. i even went as far as to download a 3rd party anti virus (AVG) and loaded pcsx2 while it was scanning with the computer shield turned on and it still allocated just fine. this computer is literally on a brand new formatted hard drive with every option i can think of turned off (superfetch, windows bitdefender, windows firewall etc) and pcsx2 works perfectly fine until i see in task manager that there is no physical free ram.

i guess the question im really asking is how can I stop or limit the amount of ram vista caches so that I don't have to restart my computer every time I leave it on too long to use pcsx2.

May 18th, 2008, 23:19	#1
techniqu Registered User Join Date: May 2006 Location: bob sagget Posts: 52	pcsx and vista ram allocation problem for some reason vista is STILL caching all of my ram (all 8gb, more than enough for vista without caching) even though superfetch is turned off. even so, it does unload ram to load up programs, but it doesn't seem to work for pcsx2. does anyone know a fix for this or a fix for this problem in vista?

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May 19th, 2008, 00:17	#2
echosierra I'm a gopher Join Date: Sep 2007 Location: Chicago Posts: 376	This issue is not as simple as you may think. Do a search, there are numerous potential causes. Do you have real-time antivirus and/or software firewall? Several are known to cause problems

May 19th, 2008, 05:13	#3
techniqu Registered User Join Date: May 2006 Location: bob sagget Posts: 52	i'm pretty sure its ram because it tells me it's unable to allocate ram, and when I check my ram 100% of it is cached/in use. this only occurs when all my ram is allocated 100% as well, and I have no virus scan programs etc activated. is there any way to stop vista from caching to my ram? i have superfetch turned off but it still keeps caching onto my ram using all of it after a while.

May 19th, 2008, 06:00	#4
echosierra I'm a gopher Join Date: Sep 2007 Location: Chicago Posts: 376	PCSX2's memory allocation can fail even with RAM is available, which is why it's hard to figure out what exactly is causing it to fail. The VM version of pcsx2 (the exe that doesn't have a 't') attempts to lock a very specific range of memory, and if for any reason it cannot you receive the memory allocation failure message. Some antivirus and firewall software are known to inhabit the range that pcsx2 wants and won't give it up, even when they are not actually scanning anything. Do you have any antivirus or firewall software at all? I'd also like you to clarify something for me. Go to the Control Panel and open up the 'System' menu, under Computer it lists your processor then the amount of physical RAM present in the system. If this number isn't 8.00 then you don't actually have 8Gb of ram, Windows only provides the illusion that you do. I'm curios because I can't think of a way to even use that much, much less do it without severely reducing the functionality of the computer.

May 19th, 2008, 10:01	#5
techniqu Registered User Join Date: May 2006 Location: bob sagget Posts: 52	yeah I tested this with all forms of protection off. pcsx2 works and absolutely only fails to allocate (currently) when all my ram is cached. it is a physical 8gb; i built this computer myself and it recognizes it as 8. the problem is that in windows vista constantly caches things I'm not using and leaves no ram for pcsx2 to allocate. this doesn't cause system slowdown because its part of vista and vista normally unloads cache when you demand ram, but pcsx2 seems to allocate ram differently on startup and vista doesn't detect it or something so it just keeps my ram cached. the problem isn't system slowdown, its just that pcsx2 won't even start because of this allocation problem. this problem only occurs when I give vista enough time to cache all my ram though, otherwise i can use pcsx2 just fine.

May 19th, 2008, 10:43	#6
nohea Registered User Join Date: May 2008 Location: Hungary Posts: 2	Um, hi guys, do not wish to hijack the thread, but i started having this same problem myself just about fifteen minutes ago so i thought i'd add my two cents as well. (And yeah, I'm new here on the forum, but not really so with pcsx2 itself.) So um, i have vista too, x64 at it, with "only" have 4gb ram, but still, so far i've been able to run pcsx2 with no problem at all, even after i started up msn and browser too... now however, all i get is this failed to allocate enough memory message, right after a fresh new power-on, even tho i basically have no program whatsoever that'd be starting up automatically with windows, except for network of course and norton 360. and yet i'm getting this message thrown in my face. which is odd tho, because v0.9.2 starts up fine at the same time; unlike 0.9.4 (or even svn351, just thought i'd mention it). so the thing is, i did no changes in system settings whatsoever and yet the program fails...um, i can't help wondering: why exactly is a specific memory range required by pcsx2 even if there's plenty of ram available, could someone enlighten me please? i'm just curious.

May 19th, 2008, 19:54	#7
Zal Registered User Join Date: Jan 2008 Location: NC Posts: 10	Vista uses a good bit of ram just with the base OS. It likes to randomly lock the range of memory pcsx2 requires, pretty much after the system is booted in my experience you won't get that range back. If you restart the system that range of memory may be freed... although it might not heh... __________________

May 19th, 2008, 21:09	#8
echosierra I'm a gopher Join Date: Sep 2007 Location: Chicago Posts: 376	Pcsx2 grabs 0x35000000-0x55000000, or something close to that. It just so happens that several antivirus and firewall software programs like to place themselves inside this range, and they don't like giving it up. The difference between the VM and the TLB version (the exe with 't') is that the VM version requires this very specific range, whereas the TLB doesn't. Not having this range means that each and every read/write to memory must be run through the translation-lookaside-buffer (TLB, get it?) to find out the physical location in RAM. The TLB translation takes time, and not having to do it is what makes the VM version faster. Even when the antivirus or firewall software isn't actively scanning or doing anything, it can still inhabit this memory range. If updating/uninstalling the offending software doesn't fix it, you may just have to stick with the TLB version. Last edited by echosierra; May 19th, 2008 at 21:15..

May 20th, 2008, 01:32	#9
techniqu Registered User Join Date: May 2006 Location: bob sagget Posts: 52	echo, as i said before pcsx2 works for the hours leading up to full ram allocation through cache. ive tested it around 3 hours after boot where I still had about 1gb of uncached ram and it allocated just fine and ran disgaea 2 perfectly at impressive framerates. i even went as far as to download a 3rd party anti virus (AVG) and loaded pcsx2 while it was scanning with the computer shield turned on and it still allocated just fine. this computer is literally on a brand new formatted hard drive with every option i can think of turned off (superfetch, windows bitdefender, windows firewall etc) and pcsx2 works perfectly fine until i see in task manager that there is no physical free ram. i guess the question im really asking is how can I stop or limit the amount of ram vista caches so that I don't have to restart my computer every time I leave it on too long to use pcsx2.