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HTG Explains: What is the Windows Page File and Should You Disable It?

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Windows uses a page file to store data that can’t be held by your computer’s random-access memory when it fills up. While you can tweak the page file settings, Windows can manage the page file fine on its own.

The Windows page file is somewhat misunderstood. People see it as the cause of slowdowns because it’s slower to use the page file than your computer’s RAM, but having a page file is better than not having one.

Image Credit: Blake Patterson on Flickr

How The Page File Works

The page file, also known as the swap file, pagefile, or paging file, is a file on your hard drive. It’s located at C:\pagefile.sys by default, but you won’t see it unless you tell Windows Explorer not to hide protected operating system files.

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Your computer stores files, programs, and other data you’re using in your RAM (random access memory) because it’s much faster to read from RAM than it is to read from a hard drive. For example, when you open Firefox, Firefox’s program files are read from your hard drive and placed into your RAM. The computer uses the copies in RAM rather than repeatedly reading the same files from your hard drive.

Programs store the data they’re working with here. When you view a web page, the web page is downloaded and stored in your RAM. When you watch a YouTube video, the video is held in your RAM.

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Image Credit: Glenn Batuyong on Flickr

When your RAM becomes full, Windows moves some of the data from your RAM back to your hard drive, placing it in the page file. This file is a form of virtual memory. While writing this data to your hard disk and reading it back later is much slower than using RAM, it’s back-up memory – rather than throwing potentially important data away or having programs crash, the data is stored on your hard drive.

Windows will try to move data you aren’t using to the page file. For example, if you’ve had a program minimized for a long time and it isn’t doing anything, its data may be moved to RAM. If you maximize the program later and notice that it takes a while to come back instead of instantly snapping to life, it’s being swapped back in from your page file. You’ll see your computer’s hard disk light blinking as this happens.

computer-status-leds

Image Credit: Honou on Flickr

With enough RAM in modern computers, the average user’s computer shouldn’t normally use the page file in normal computer use. If you do see your hard drive start to grind away and programs start to slow down when you have a large amount open, that’s an indication that your computer is using the page file – you can speed things up by adding more RAM. You can also try freeing up memory — for example, by getting rid of useless programs running in the background.

Myth: Disabling the Page File Improves Performance

Some people will tell you that you should disable the page file to speed up your computer. The thinking goes like this: the page file is slower than RAM, and if you have enough RAM, Windows will use the page file when it should be using RAM, slowing down your computer.

This isn’t really true. People have tested this theory and found that, while Windows can run without a page file if you have a large amount of RAM, there’s no performance benefit to disabling the page file.

However, disabling the page file can result in some bad things. If programs start to use up all your available memory, they’ll start crashing instead of being swapped out of the RAM into your page file. This can also cause problems when running software that requires a large amount of memory, such as virtual machines. Some programs may even refuse to run.

In summary, there’s no good reason to disable the page file – you’ll get some hard drive space back, but the potential system instability won’t be worth it.

Managing the Page File

Windows automatically manages the page file’s settings for you. However, if you want to adjust your page file settings, you can do so from the Advanced System Settings window. Click Start, type Advanced System Settings into the Start menu and press Enter to open it.

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Click the Settings button under performance.

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Click over to the Advanced tab and click the Change button in the Virtual memory section.

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Windows automatically manages your page file settings by default. Most users should leave these settings alone and allow Windows to make the best decision for you.

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However, one tweak that may help in some situations is moving the page file to another drive. If you have two separate hard drives in your computer, assuming one is the system drive with your programs installed on it and one is a less-used data drive, moving the page file to the data drive can potentially offer some increased performance when your page file is in-use. Assuming that Windows will already be using the system drive if it needs to use the page file, this spreads out the hard drive activity instead of concentrating it on one drive.

Note that this will only help if you actually have two separate hard drives in your computer. If you have one hard drive separated into multiple partitions, each with their own drive letter, this won’t do anything. Whether it’s partitioned or not, it’s still the same physical hard drive.


In summary, the page file is an essential part of Windows. Even if it’s rarely used, it’s important to have it available for situations where programs are using an unusually large amount of memory.

Having a page file won’t slow down your computer – but if your computer is using its page file a lot, you should probably get some more RAM.

Chris Hoffman is a technology writer and all-around computer geek. He's as at home using the Linux terminal as he is digging into the Windows registry. Connect with him on Google+.

  • Published 10/11/12

Comments (35)

  1. Sarunas

    I think there is an error “Windows will try to move data you aren’t using to the page file. For example, if you’ve had a program minimized for a long time and it isn’t doing anything, its data may be moved to RAM.” moved to RAM or page file ?

  2. TechGeek01

    I may be wrong here, but didn’t you post this article awhile back?

  3. Ahmad

    Good article but there are few points that should have been cleared out.
    1. I have 16GB of RAM. this means that the size of my page file will be something near that. It took almost all space on C drive so I had to disable it
    2. When data is being copied from minimized apps from/to the hard drive, other programs trying to read/write from the hard drive will be slow waiting for the paging operation.

    Regards from Syria.

  4. steven

    A Myth i have heard is that disabling system page file and then running a defrag can help as defrag automatically skips an files regarding the reserved space for the page fileby deault, and that defragging it and then reenabling the pagefile helps….. is there any truth to this??

  5. rKiller

    Huuuu…..I am sure that can’t be done in CMD? Or can it?
    -Actually it can be done and is extreamly useful!!

  6. Burned
  7. Gary

    I also believe if using a SSD, should have been brought up.

  8. Grant

    One thing to consider is SSD. if you have one, the page file will be very fast, which is good, but you also need to balance the limited write cycles of SSD. If you have SSD, it may be best to add RAM to at least reduce page file usage, if not eliminate it, or if you have both, take the performance hit and tell the operating system to put the page file on a magnetic media.

  9. Orlando

    You failed to mention that page file may act differently in an SSD. For example, I have 8GB of ram with a 256GB SSD. When I set a page file on it, the performance was effected significantly. However, when I disabled the page file, my system performed much smoother.

    Overall, if you have 8GB ram with an SSD..you don’t need the page file. I have two Virtual machines running with several other programs with absolutely no issues.

    Test what works out for you!

  10. MdKnightR

    This isn’t entirely true – “Note that this will only help if you actually have two separate hard drives in your computer. If you have one hard drive separated into multiple partitions, each with their own drive letter, this won’t do anything.” I had a situation at my new job where several of the older PCs out in the plant had been set up with a separate Windows partition that was severely limited (only 10 GB). While the machines aren’t powerhouses, they shouldn’t be bogged down with what they’re used for out on the floor. Just by moving the page file from the hidden Windows partition on C: to a new location on D:, it was akin to that scene in Star Wars where the Millennium Falcon is struggling to get to light speed, then it suddenly works!

  11. spike

    I have an SSD and tons of RAM, I have the pagefile disabled to reduce writes to the SSD, and haven’t had any issues.

  12. Anthony

    I had heard specifying a fixed size for the page file (1.5 times RAM) was optimal. Is that all true. Also, I have found that Windows 7 still keeps a small page file on C: drive when setting it to be somewhere else. Do you know anything about this?

  13. Davey126

    While SSDs do have a limited number of write cycles the maximum on modern SSDs is of no concern to most consumers (you can read up on the technology elsewhere). I let Windows manage the pagefile size on machines with less than 4GB or RAM and set min/max values on machines with larger amounts. The actual number of page file writes is relatively small on machines with adequate memory and Windows 7 is quite intelligent with memory management. In my view there is no reason to disable the pagefile except in specialized circumstances.

  14. clamo

    if you have A SSD you should not have the page file enabled at all, as this WILL slow down system performance. if you are using ANY old HDD they leave it on. and RAM has nothing to do with the windows system paging file. what this file does for windows application is ADD cashe support for programs that are to much for your system RAM to hold. like for example: if you have a small amount of RAM in your system, windows will use more HDD space for on the fly access “DO TO” limited physical RAM. the more RAM you have the less windows uses this file to cashe programs in use. the major con when using SSD’s and having this disabled is when running programs that require more that 6-12 gig’s of ram is, if you are running a computer on say only 4gig’s of RAM your system will lock up really fast because windows can’t cashe ANY files to the SSD.

    but as far as SSD’s having a limited # of write scales depends on witch one you buy. Hi end SSD’s don’t have this problem, but cheaper ones do. that’s y its a good idea to look in to things before you buy.

  15. tomko44

    I had always heard that using a fixed size to the pagefile (heard various amounts based on RAM) and then defragging the drive would help performance. Of course that was back in olden days when 8gb or more was pretty much unheard of.

  16. Bill

    However, disabling the page file can result in some bad things. If programs start to use up all your available memory, they’ll start crashing instead of being swapped out of the RAM into your page file.

    This is actually one of the reasons I *DO* disable the page file. I want that memory hogging app outta there! If the app is that bad it will eventually crash when it fills up ram AND the page file. Until then, the machine slows to a crawl or is unusable anyway.

    Caveat: I only disable the page file on machines with at least 8Gb of ram, and always disable it on machines with 12Gb or more.

  17. bemymonkey

    On HDD based machines with 8+ gigs of RAM, there is a noticeable difference when turning the page file off… due to:

    “Windows will try to move data you aren’t using to the page file. For example, if you’ve had a program minimized for a long time and it isn’t doing anything, its data may be moved to RAM. If you maximize the program later and notice that it takes a while to come back instead of instantly snapping to life, it’s being swapped back in from your page file. You’ll see your computer’s hard disk light blinking as this happens.”

    Windows 7 is too aggressive in paging out data – if you look at the performance tab of your task manager after a week or two of uptime with regular use, you’ll notice that your commit charge is much higher than your used physical memory – the excess is all in your page file. Even on my desktop with 16 gigs of RAM, I still get hard drive churning when restoring previously minimized applications… turning off the page file (or setting it to 512MB) solves this.

    Of course, on SSD based systems this is pretty much irrelevant (as long as you don’t care about the additional write cycles) – with the Samsung 830 in my laptop, swapping is so fast it’s almost unnoticeable.

  18. Herb

    I’m not a techie and really don’t understand the difference between manage”automatically” or “system managed size.” Both must behave differently … Can someone explain this? Thanks.

  19. Crasher

    With systems that have plenty of RAM I always disable the swap file. I find it IS faster and I have no issues except if I try to run a heap of VMs or other things that use lots of memory. They don’t crash I just get a warning that memory is getting low.
    Swap files are so yesterday for the days when RAM was expensive. Pay $50 for * GB + and turn it off

  20. Jason

    @tomko44 On a system with 2GBs or less of RAM, you’re more likely to run into situations where Windows doe a lot of paging. In this scenario, a fixed-size page file can be a tremendous performance benefit. In systems with 4GB+, paging is generally pretty rare (depend in on your usage) and so the old wisdom no longer applies to everyone. Keeping a small page file that Windows is allowed to expand in a worst-case scenario is not going to negatively impact performance 95% of the time and can save your bacon the other 5%.

  21. Krunk_FU

    Also moving the page file off the OS drive will result in you not getting a dump file in case of a BSOD. Just a note for people that care about those things (my employer).

  22. r

    …18 gb of ram & two SSD’s (256gb) but I still keep a small 1024 page file, probably never use it but I don’t care

  23. Ido

    I have 16GB RAM on my machine, and Windows does use the Pagefile quite often, despite having plenty of RAM available. An article I read about this (can’t remember where, so I can’t reference, sorry), suggested Windows does that to make sure there would always be enough free RAM for new allocations, whenever necessary. In other words, Windows won’t wait for your RAM to fill up before starting to use the Pagefile.

    Regarding moving the Pagefile to another drive, I took it one more step forward. I have 5 physical drives on my machine, so I split the Pagefile between two of them (the least busy ones). The problem is that those two drives are relatively slow (WD Intellipower =~ 5400RPM), so I’m not 100% sure that this is the best way to go.

    BTW, make sure never to split the Pagefile between two or more partitions of the same hard drive, since as far as I understand, it would hurt performance big-time. Hard drives are like us, men – they suck at multitasking. :)

  24. hfxmike

    There was no mention of setting the minimum and maximum pagefile size to the same amount. I remember seeing mentioned as a tip a lot. Is it still valid? Or does it matter?

  25. Terry

    I only recently tried to run my Win7 computer with 4GB of RAM. And I did not notice any difference in operation except in one area. Making a system backup. Using Macrium it would normally take about an half hour (64GB used of a 500GB hard drive). I started it up and it claimed it was going to take 10 hours. So I tried Windows built in backup. Started it in the morning and it didn’t finish till after I went to bed at around 11:30pm. I re-enabled it. My formula for setting : 1024 x amount of memory x 1.5. Then I set the min and max amount the same.

  26. Jer

    Yepper!

    Buy a cheap SSD (lowest capacity possible), use Windows settings to direct your pagefile to be stored there. You’ll notice the difference when you have a lot of your apps open, or when using something that uses huge amounts of RAM, i.e. Photoshop, etc, No SSD, short-stroke an old HDD from your scrap pile and use it. Old WD Raptors work great for this! For those of us with spread parity RAIDs, this is a good thing. If your RAID is hardware controlled your pagefile writes are done multiple times keeping your HDDs busy. I utilize a RAID 5 configuration, as soon as I moved all the Windows temp junk and pagefile to the spare non RAID disk, the active disk time was noticeably less. Setup up multiple Gadgets to monitor your scrap/scratch drive and you’ll see how much its used.

  27. /\ |\| () |\| Y |\/| () |_| S

    One thing not considered here are RAM drives and file/drive fragmentation!

    If you have ungodly amounts of RAM, like 32Gig and use half (16G) for a RAM drive, you probably want to use it to place your page file on. However, you might discover that you can’t easily move your page/swap file there – because it’s RAM! And RAM is the very thing these page files were invented to supplement. So under more rare circumstances, like situations where an entire build of Windows could be placed in a RAM drive, it makes sense to disable the page file. But again, those are rare cases.

    We also need to consider Solid State Drives (SSD’s) too! As you may know, these drives are nothing but non-volatile RAM – which is way faster than any hard drive. And very often, it is recommended to disable the page file on a SSD if at all possible. True, an SSD is not system memory but SSD’s do tend to wear out prematurely when they are constantly accessed like when a swap file is used. And all too often, the recommendation is to move the swap file to a conventional hard drive if for no other reason than to prevent this premature wear and tear. (BTW, Windows 7, so far as I know, is the only OS that seems to try and move the page file around on a SSD [no thanks to TRIM either] so that this wear and tear is evenly distributed).

    And then there is a little matter of file/drive fragmentation. The article says nothing about it. Because it may be necessary to temporarily disable the swap when you’re trying to defragment things and get the page file to use one contiguous part of the hard drive. And for the most part, Windows does that. But if you don’t hard set or “allocate” the most space possible for the page file then it does tend to get fragmented over time. Leave the page file settings at their defaults and Windows will always be trying to adjust the page file size which is why it can get fragmented. Of course, the downside to hard setting a page file is when you may need more “swap” space to use with your RAM – because you’re the type of user who never closes anything or use programs that require a lot of RAM to begin with.

    But for the most part, people who don’t have huge amounts of RAM, or SSD’s, or even bad computing habits, I agree with the advice – leave the page file settings alone. Just know that there are (valid) reasons when you may want to tweak it or even eliminate it.

  28. faded

    I see no point of disabling paging, it’s a fail safe. If you have godly amounts of ram, you will probably never use the paging system even if it’s turned on. But lets say you do fill up RAM, it’s just going push unused/lowest priority to swap. Why wouldn’t you want that?.. This is standard memory management/virtual memory…

  29. Neil

    I see issues with pagefiles getting fragmented – each time Windows changes the size of the pagefile there is the risk that it will get fragmented, as there will almost certainly be no space behind it to expand into. This happens even with a relatively empty disk and gets certain with a fuller drive. If paging is slow, paging to fragmented pagefile is much slower! Windows own defragger can’t sort it out, but a boot time defrag (for example by Defraggler or PageDefrag) will fix it if there is enough clear space on the disk. The way to prevent this? Fix the page file as mentioned above. As a matter of course I fix the min & max size manually at the Windows recommendation for maximum size.
    My own (Win7) laptop runs 8GB RAM – I don’t have a pagefile and have not had any problems – routinely having multiple applications running and often 20 Internet Explorer tabs running. This did seem to speed the machine up, but there also was a side benefit of increasing battery run time – from the reduced HDD churning.

  30. Betco1

    Can you use an external HDD in place of a SSD.

  31. ahmet

    guys, do you know how to change the paging strategy of windows, because after i have about 85% ram usage, my pc gets sooo slow, because windows gets in alarm mode, and moves everything to the harddisk to make free ram space. I want to adjust this value, and let windows do this alarm mode at 95% or so, and not 85%. Is is possible to tweak this somewhere in the registry?

  32. Sam

    If one of the reasons for the existence of the paging file is for swapping out parts of programs when RAM starts getting full then why does Windows increase the size of pagefile.sys in lockstep with the amount of RAM installed?

    For example in a machine with 4GB RAM installed the Windows-managed pagefile.sys ends up being 4GB. So then if that machine is upgraded 16GB and rebooted I find that the Windows-managed pagefile.sys is now 16GB. This seems counter-intuitive to me since theoretically the computer should be less likely to run out of memory when the amount of RAM in it has been increased.

  33. BigT

    Thanks for shedding some light on the Myth. Her’es the tuth, depending on what you’re doing you may or may not need the pagefile that much. But let’s just say… if you have it and don’t use it then disablining won’t really affect anything. How ever if you come up when you suddenly need it, then you will have many shed tears .

    As for for on a separate, although it means less now with SATA and SATAn, but with IDE you needed to keep the pagedrive on a different IDE channel altogether for any benefits due to the arrangements between Master and Slave Drives.

    Tweaking the size of the Pagefile. It depends, The page file should be about 8gb for most people running Windows7.And for performance boosting, keep the size fixed (though this will take some experimenting. FIxing the pagefile size will in fact remove the need to defragment since the space is allocated in one contigious block. This is done by simply setting the minimum and maximum size to the same value.

    The benefit. the OS will not spend time resizing it. The data will not beome fragmented. The downside. you lose that much of your HD space . If your needs exceed this… things can get messy.

  34. Dave P

    Thanks for the Page File info.
    Something everyone should also consider is; ‘How to Clear the Windows Paging File at Shutdown’. If your PC uses the Page File, scraps and remnants can be left over after shutdowns, crashes, etc… The Page file can become large and corrupt. This tip from Microsoft Tech Net will help clean out the old to make room for the new. This link will explain the process and even do it for you, if you preferr.
    http://support.microsoft.com/kb/314834
    This made a world of difference on my PC.
    NOTE: this will make Reboot and/or shutdown a bit slower at times, as it clears out the Page File.

  35. docBrian

    The paging.sys file is used by the Windows implementation of virtual memory. It’s similar to the “swapfile” used by UNIX/LINUX systems to implement virtual memory. You DO NOT want to disable the paging file.

    Here’s what you should do to maximize performance:

    1. Add a high speed second non-system drive to your system. Ideally, this should be an SSD drive. Alternatively, this could be a multi-spindle RAID 0 array.
    2. Format the drive.
    3. Create a contiguous paging file on the second non-system drive.
    4. Use the “Custom size” option to set the initial size and maximum size of the paging file to the same values. Start with the size recommended by Windows. You may find that a smaller size works for you without sacrificing performance. Or you may may need a larger size, especially if you are working with programs that benefit from lots of RAM, such as Adobe Photoshop. Empirical tuning of the swap file (pagefile.sys) requires minimizing the “page faults” generated by the OS during memory-intensive operations.
    5. Restart the system and experiment with different pagefile sizes.

    You can never have too large a pagefile; the OS will simply use what it needs. But if your pagefile is too small, performance will suffer, and you may experience kernel panics (BSOD).

    I’m a professional engineer, and have worked as a kernel engineer on SMP UNIX workstations. So I know what I’m talking about.

  36. William Henry

    It seems to me if you have more than 4 Gig of RAM, then you are using a 64bit system and if you have 8 Gig or more you don’t need virtual memory.

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