XP Memory Management = FAIL

[Th3_uN1Qu3]

I'm sorry i haven't snapped a printscreen.

So i was on this here computer, P4 1.8GHz @ 2.46, 768 RAM, Win XP SP3. I was only running Yahoo Messenger and Opera with just 3 tabs. Background services are some Canon printer and Avira antivirus (this isn't my computer).

I opened up an embedded youtube vid. The system froze for a few seconds, then as it resumed a message appeared at the right side of the taskbar. "Windows: Virtual Memory Minimum too low. Windows is increasing the size of your virtual memory paging file."

WHAAAAAAAA???? Ctrl-Shift-Esc and check the Performance tab. Under "Available" there was a whopping 520MB of RAM. So, um, what business do you have with the pagefile exactly?

So, stop bitching about the memory usage of Vista and Win7, at least the RAM that you paid for actually gets used in those OS. Linux has been using as close to 100% RAM as possible for ages, only freeing it on demand. Aka just what MS does with Superfetch. Never heard anyone whine about Linux memory usage...

[mariushm]

Re: XP Memory Management = FAIL

It's bug in Flash, related to hardware video acceleration of videos. If you disable that in Flash, you'll trigger that less often.

The video driver maps memory so that video frames can be transferred to the video card memory for hardware decoding and something goes wrong (something like Flash signaling the video is 16k x 16k @ 120fps)

Happened to me as well in Windows 7 and Windows 2003 so it's not related to XP and you didn't see the memory as used because the video driver probably crashed and restarted itself by the time you saw the memory warning from Windows.

[brethin]

Re: XP Memory Management = FAIL

This isnt a problem with XP but with more to do with users expecting systems with small amounts of memory to run todays software with no problems. Virtual Memory and Available Memory are 2 different things so pointing to the fact you had 520MB of available memory when you got a virtual memory too low warning is pointless. This can happen with any OS (see Mariushm's post). You have 2 options, add more ram to the machine or stop running memory intensive software on it. Blaming XP just makes you look stupid.

[RJARRRPCGP]

Re: XP Memory Management = FAIL

"Windows: Virtual Memory Minimum too low. Windows is increasing the size of your virtual memory paging file."

-> Probably the anti-virus software <-


Just hope you're not using McAfee! There's a known issue where scanning files causes that.
And followed by this error message from Windows:

MCSHIELD.EXE has generated errors and will be closed by Windows.

->Or<-

MCSHIELD has encountered a problem and needs to close.

-----------------------------------------------

But, I wouldn't be surprised if the anti-virus scanning is causing that type of horseshit!

Sorry, it looks like it's time to dump Avira.

[momaka]

Re: XP Memory Management = FAIL

I get that Virtual Memory message on my main PC when my RAM usage goes above 320 MB or so and I let the computer sit for a while without doing anything. Reason it happens is because XP decides to put some of the stuff I'm not using in the pagefile, which is only 160 MB initially (384 MB expanded). Why so little? - well, I only have 384 MB of actual RAM, and In order to make the computer more responsive, I keep the pagefile small so that XP uses the RAM slightly more. And from my experience, XP doesn't work too well with pagefiles larger than 512 MB anyways, so why bother.

[lti]

Re: XP Memory Management = FAIL

That is better than the latest version of Norton. The performance alerts are too sensitive. On a computer with Norton, open Internet Explorer and don't touch anything. After ten seconds, Norton will tell you that Internet Explorer is using too much memory. Also, the performance alerts take up almost one-fourth of the screen, but the actual malware warnings use as little screen space as possible using an 8-point text size.

McAfee has been a CPU and RAM hog for a long time. Also, it runs a scan when the computer boots up if the computer has not been used for a few days. If you have an older computer with a single-core CPU, the computer will be unusable for a few hours.

The original problem is strange. I haven't seen that message on a computer with Windows XP SP3 and more than 256MB of RAM.

[dood]

Re: XP Memory Management = FAIL

That is better than the latest version of Norton. The performance alerts are too sensitive. On a computer with Norton, open Internet Explorer and don't touch anything. After ten seconds, Norton will tell you that Internet Explorer is using too much memory.

I just got a message from AVG Free 2012 that said IE was using too much memory (~200mb), and that I should close and reopen it. I had 2 tabs open... Facebook, and this forum. I have over half of the 3gb of physical memory open... really, what is closing and reopening IE going to do for me?!

[weirdlookinguy]

Re: XP Memory Management = FAIL

lol antivirus

[Uranium-235]

Re: XP Memory Management = FAIL

XP will use a paging file, even if you disable it, so will vista. I believe win7 is the real first winOS that can truly use no paging file without hacking of some kind

the xp memory manager does have issues. but there was windows 98 mm, which was TERRIBLE

[Th3_uN1Qu3]

Re: XP Memory Management = FAIL

you didn't see the memory as used because the video driver probably crashed and restarted itself by the time you saw the memory warning from Windows.

The video card is a GeForce 4 MX. I don't think that even has a self-restarting driver.

You have 2 options, add more ram to the machine or stop running memory intensive software on it. Blaming XP just makes you look stupid.

This machine runs exactly the same with 768MB than it did with 256MB which it used to have. That should tell you something. And don't tell me 768MB isn't enough to watch youtube, because i don't believe you.

Sorry, it looks like it's time to dump Avira.

It's not my computer so i'll just leave it as it is... Btw, this computer was also set to a small pagefile (384MB). I bet that if i set it to no pagefile at all it'll quit whining... What i did instead is made the pagefile minimum 1GB and maximum 2GB. Hope that's enough "virtual memory" for you...

But anyway, most of you have missed the point - XP's memory architecture still stems from back in the days of 9x, when RAM was scarce and very expensive. It is programmed to use the pagefile before RAM. This becomes very obvious when you're running a HDD-intensive program such as a defrag. Everything slows down to a crawl because the system is continuously hitting the pagefile while the defrag makes drive access very slow, when you've got like half your RAM sitting there unused.

The caching system in Vista and 7 is a step forward, but there's still room for improvement. Waiting for Windows 8.

[mariushm]

Re: XP Memory Management = FAIL

I'm sorry but you're wrong there.

Windows XP was made when it was already common to have workstations with 4-8 GB of memory and servers with up to 32 GB of memory. In fact, even the 32 bit version of Windows 2000 which was made years before Windows XP is capable of running with up to 64 or 128 GB of memory - I forget the exact values now.

Windows 98 had some bug (or you could say it "performance tweak") which made the kernel unable to access data in pagefile over the 512 MB limit - it would only read and write the first 512 MB of page file. It was somewhat intentional, from the days of Windows 95 and running on systems with as low as 4 MB - in order to make the kernel use very little memory, Microsoft used the upper bits on 32 bit variables to hold some internal stuff so the maximum paging file it could use was 1FFF FFFF or 512 MB-1.

Windows XP, as it's based on the Windows NT kernel, is completely different in regards to paging but like previous operating systems from Microsoft, it needs a page file available, even if it's never going to be used because you have plenty of RAM.

It's hard to explain but basically, there are some algorithms inside the kernel which take different programming paths based on the availability of a page file - without one, even if you have a ton of memory, there's an almost unnoticeable performance hit.

When a program is active, Windows tries as much as possible not to swap to pagefile when there's memory available.

You're not getting poor performance because it pages during defrag, but rather the system becomes slow because the defragmenting program works with the file system in low level mode (edits file allocation tables, reads and writes sectors) so file caching is disabled. It's like using Windows 95 or Windows 98 without smartdrv.exe - if you're old enough to know what that used to do.

The defrag tool keeps a list of empty sectors in memory and moves fragmented files into these empty sectors, then it edits the file allocation table saying where the first byte in the file is now located. After the file allocation table is successfully edited, it marks the old sectors as unused. But, when writes to disk occur, the service has to stop and re-check the empty sectors it selected for writing the file it tries to defragment and if a write occured in one of those sectors it has to look up for another continuous area of disk space.

Another argument for poor performance during defrag is that simply put, Windows XP is optimized towards programs and not services. (you can change this from the advanced options, right click on My computer, properties, advanced... I think)

On Windows XP, the defragmenting tool is a service - what you see when you defragment is basically a dumb GUI that receives signals from the service and shows them on the screen.

By default, Windows XP will tend to page memory used by services to disk much faster than the memory used by programs (like browsers, winamp or whatever player you have) so if you tab between programs or visit websites, inadvertently Wndows will start to move to page file stuff used by the defragmenter and in turn the defrag tool has to stop and re-read the disk surface.

Best strategy for a page file on Windows XP is to set it to a fixed size page file, generally about 150% the size of the RAM and less than 4 GB for each page file (you can create multiple page files). For a system with 768 MB of memory, 1 GB is enough for most cases.
After a reboot, you can run a defrag using a good application like O&O defrag, which will move the page file to the start of the partition, so you'll have the lowest disk access. If it's variable size, the defrag will move the pagefile to the middle of the partition, to give it the best chance to expand without fragmenting itself.

[Th3_uN1Qu3]

Re: XP Memory Management = FAIL

You're not getting poor performance because it pages during defrag, but rather the system becomes slow because the defragmenting program works with the file system in low level mode (edits file allocation tables, reads and writes sectors) so file caching is disabled. It's like using Windows 95 or Windows 98 without smartdrv.exe - if you're old enough to know what that used to do.

Yes i know what that does. Also, IMO, Win98 was the best version of Windows - heck, there still is an active Win9x community and the improvements made by fans almost rival what the open-source guys do.

I'm also *not* talking about the built-in defragmenter.

Best strategy for a page file on Windows XP is to set it to a fixed size page file, generally about 150% the size of the RAM and less than 4 GB for each page file (you can create multiple page files). For a system with 768 MB of memory, 1 GB is enough for most cases.

That's the old way of handling it. A system with less memory will always need a larger page file than one with more - as a matter of fact i have disabled the page file on my dual-PIII with 2GB of RAM and it's worked out very well.

If you're not using any memory-intensive programs, having more than 1GB RAM in XP is completely pointless. Just like i said before - Superfetch in Vista and 7 is a step ahead, but it's not "there" yet. Then again, with SSDs becoming mainstream, we won't have to worry about all this anymore...

[RJARRRPCGP]

Re: XP Memory Management = FAIL

I'm sorry but you're wrong there.

Windows XP was made when it was already common to have workstations with 4-8 GB of memory and servers with up to 32 GB of memory. In fact, even the 32 bit version of Windows 2000 which was made years before Windows XP is capable of running with up to 64 or 128 GB of memory - I forget the exact values now.

Windows 98 had some bug (or you could say it "performance tweak") which made the kernel unable to access data in pagefile over the 512 MB limit - it would only read and write the first 512 MB of page file. It was somewhat intentional, from the days of Windows 95 and running on systems with as low as 4 MB - in order to make the kernel use very little memory, Microsoft used the upper bits on 32 bit variables to hold some internal stuff so the maximum paging file it could use was 1FFF FFFF or 512 MB-1.

Windows XP, as it's based on the Windows NT kernel, is completely different in regards to paging but like previous operating systems from Microsoft, it needs a page file available, even if it's never going to be used because you have plenty of RAM.

It's hard to explain but basically, there are some algorithms inside the kernel which take different programming paths based on the availability of a page file - without one, even if you have a ton of memory, there's an almost unnoticeable performance hit.

When a program is active, Windows tries as much as possible not to swap to pagefile when there's memory available.

You're not getting poor performance because it pages during defrag, but rather the system becomes slow because the defragmenting program works with the file system in low level mode (edits file allocation tables, reads and writes sectors) so file caching is disabled. It's like using Windows 95 or Windows 98 without smartdrv.exe - if you're old enough to know what that used to do.

Actually, you mean Windows 3x without smartdrv.exe lol.

Windows 95 always has built-in cache by default. The first Windows version to have VCache always enabled.

And Windows 9x seems to have a limit at 768 MB.

Noticed a strange bug where setting the swap to bigger than 768 MB on Windows 9x, causes a false error message about there not even being sufficient RAM to start Windows!

[ratdude747]

Re: XP Memory Management = FAIL

well, on my dell latitude d400 (1.8ghz pentium M donthan, 2gb pc2100), it was running slow...

and look what I found:





why???

[yyonline]

Re: XP Memory Management = FAIL

why???

Because the graph is wrong, or mislabeled rather. "PF Usage" in XP task manager is actually measuring the commit charge. Commit charge in Windows is the size of the virtual address space. It doesn't tell you how much of the virtual address space is stored in memory vs. on disk. The graph has actually just been renamed "memory" in newer Windows versions.

Not that Wikipedia is the most reliable of sources, but it explains the whole thing quite clearly, and I know this to be true.

In the Task Manager utility under Windows XP and Windows Server 2003, the graphical displays labeled "PF usage" and "Page File Usage History," despite their labels, reflect not the pagefile contents but the total (or current) commit charge. The height of the graph area corresponds to the commit limit. These do not show how much has actually been written to the pagefile, but only the maximum potential pagefile usage: The amount of pagefile that would be used if all current contents of RAM had to be removed. In Windows 2000 and Windows NT 4.0, these same displays are labeled "Mem usage" but again actually show the commit charge and commit limit. Similar displays in the Task Manager of Windows Vista and later have been changed to reflect usage of physical memory.

http://en.wikipedia.org/wiki/Commit_charge

As for Th3_uN1Qu3's original post - I suspect a memory leak in one of the programs you were running. XP will increase the page file size any time the commit charge approaches its limit. Even though physical memory was available, there wasn't enough space in the page file to swap out all the memory contents *if needed*...XP does this proactively. There were probably some inactive programs already swapped out to disk taking up space in the existing page file, and not enough space to fit the active programs in memory *if* they needed to be swapped out.

[ratdude747]

Re: XP Memory Management = FAIL

well, i see. the hdd was fragmented beyond belief so auslogics is doing some janitorial work... slownesss cause?

[shovenose]

Re: XP Memory Management = FAIL

Upgrade your 9 year old XP to Windows 7 and it's a moot point.

[yyonline]

Re: XP Memory Management = FAIL

None of the numbers on that tab tell you how much of your virtual address space resides in the page file.

[ratdude747]

Re: XP Memory Management = FAIL

Upgrade your 9 year old XP to Windows 7 and it's a moot point.

Why? I only get 2 copies of 7 for $30 per year (my college setup gave me 2 .edu emails to use). Once I redeem those I will be upgrading my main desktop and my main laptop... this old d400 doesn't need 7... so unless someone else is footing the bill, it ain't happening.

[ratdude747]

Re: XP Memory Management = FAIL

None of the numbers on that tab tell you how much of your virtual address space resides in the page file.

I figured out my error and hence the post edit. read the post again.