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Mike BroderickFlag for United States of America

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XP Page File setting, System Managed Sized question

On XP, under Page FIle settings, if you select System Managed Sized, is there a maximum page size (I have hundred gig or so of available disk space)?

I had a PC lock up a couple of times. Looking at the event log, the last messages were apps that got errors that looked like the page file was full. I changed the setting from values I had to  "System Managed Size". My question is, how does System Managed Size work? For example, does it calculate a minumum and maximum page size for you, and adjust those values each time you IPL, or does it assign a min and max page size and leave it?

Thank you.
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"The metric you need to observe in this scenario is your Commit Limit. This tells you what amount of maximum memory would be committed to disk *IF* it had to at one time. This will never happen(actually it cant) so you can base your page file size off that number.

So for example, start with your page file the same as the amount of ram in your system, i.e. 4 gigs. Monitor your commit limit in task manager for a few days during "full load". If your commit limit only reaches 3 gigs, you could trim that page file down some. This helps with the excessive pages. "

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Thank you, but at this time I'm interested in exactly how System Managed Size works.
When the system boots up, the Session Manager process determines the list of page files to open by reading the value in the HKLM\System\CurrentControlSet\Control\Session Manager\Memory Management\PagingFiles.  This value contains the name of the paging file as well as the minimum and maximum size of each paging file.  Windows supports up to 16 page files.  On a 32-bit system running the normal kernel, the maximum size of each page file is 4095 MB.  On x64 systems and x86 systems with the PAE kernel, the maximum page file size is 16 terabytes (16TB).  On IA-64 systems, each page file can be as large as 32 terabytes.
In the simplest terms, the System Managed Page File allows Windows to automatically adjust the page file depending on the current demand. If it reaches the physical (or software) limits, your computer will crash. This should never happen, and if it is, you probably have a virus.
That sounds like what I want. I am not lookingfor razer-thin performance adjustments, just avoiding glaring mis-adjustments.

How often do these adjustments to the page file occur (every few miliseconds, once an hour or day, etc)?

Is there any large disadvantage to using the System Managed setting?
I have never noticed a performance difference. If system managed scares you, set the page file to a minimum size of your total physical memory, and a max size of 2 x your physical memory.

You should never run out of page file memory when it is set to system managed (I recommend you use this setting), if you are running out it indicates a software problem (most likely a virus).

Check the Task Manager to see what program is using all of your memory.
On XP I prefer to set minimum and maximum manually - I set them to be the same size. You can figure the size you need from the info above. (I usually go with RAM*1.5 and see what happens. This keeps the pagefile in one place (and not fragmented)
But first I usually try to set the page file to 0, defrag my hard drive and then set pagefile as above. This creates (as long as you are not really low on disk space) a non fragmented page file.
If you allow Windows to manage it will expand and reduce the pagefile over time causing more disk activity and fragmentation.

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agamal, that is great news, it is how I do it (as my comment above) I forgot to mention the C: part, that is very wise though there can be performance gains to move the pagefile to another drive (but yes you will lose the dumpfile capability)