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tigermattFlag for United Kingdom of Great Britain and Northern Ireland

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Page File usage when RAM is free

I'm a little confused. If you will note my attachment to this question, you'll see that my system is using about 600-700MB of Page File, when it quite clearly has well in excess of 2GB of System RAM free for use.

My understanding of the page file is that it is used as a storage location when RAM becomes full, and some space needs to be created in RAM for new data.

Is my understanding wrong? Am I interpreting the data in Task Manager incorrectly? Why? Why not?
And the root question, why would my system page off to disk if there is RAM free?

Maximum points for this one (500) for a detailed answer! Thanks.
task-manager.JPG
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Dirtpatch-Jenkins

Virtual memory is created using a special file called a swapfile or paging file.

Whenever the operating system has enough memory, it doesn't usually use virtual memory. But if it runs out of memory, the operating system will page out the least recently used data in the memory to the swapfile in the hard disk. This frees up some memory for your applications. The operating system will continuously do this as more and more data is loaded into the RAM.

However, when any data stored in the swapfile is needed, it is swapped with the least recently used data in the memory. This allows the swapfile to behave like RAM although programs cannot run directly off it. You will also note that because the operating system cannot directly run programs off the swapfile, some programs may not run even with a large swapfile if you have too little RAM.

So once something is stored in the pagefile it stays until it gets "pushed" out when needed.
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Thanks for your description. However this is occurring pretty much after starting the system and without loading too many intensive applications. If I watch my Physical RAM usage, it never drops to a level whereby the OS is 'running out' and needs to page.

Is there some special level or % which the OS will try to keep in free RAM?
nice question Tigermatt have seen this before but never thought of asking here.Want to see what the experts would come up with.
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Dirtpatch-Jenkins

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And of course, it does this for a reason... it tries to anticipate loads...

say your running your browser, which is not a heavy load.. the system may page files for use later..

you decide to kick on your dreamweaver and visual basic at once...well more ram is free to handle that because paging was utilized properly to begin with,, rather than things having to be swapped on the fly.
You can visualize it like the windows OS itself... Its running on the .net framework - all kinds of functions are partitioned off into dll's  , when a procedure needs to do  "x" it calls on the appropriate .dll.

If the OS had to load all the functions held in the various .dll's it would be a behemoth.

So the paging file is used even when ram is free for much the same reasons,, kind of a load balancing to maximize available resources.
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Thanks guys. So essentially, what we are saying here, is it is perfectly normal for my Page File usage to be up around 600MB after starting my PC?
Yes,, perfectly.