Page File
- Thread starter life24
- Start date
mikeymikec
Lifer
- May 19, 2011
- 19,911
- 14,156
- 136
A page file of an automatically determined size is automatically created when Windows is installed. I imagine that if RAM is upgraded, the size of pagefile.sys is re-evaluated.
Just because pagefile.sys is ~3GB in size, it does not mean that Windows has paged 3GB of memory to disk. As I understand it, it's quicker to write to a file that has been already created and is the correct size rather than having to make additional requests to allocate more file space to a file then write the necessary data. Also, it's less likely to get fragmented if it never needs increasing in size.
I'm curious about the existence of swapfile.sys in that list though.
Just because pagefile.sys is ~3GB in size, it does not mean that Windows has paged 3GB of memory to disk. As I understand it, it's quicker to write to a file that has been already created and is the correct size rather than having to make additional requests to allocate more file space to a file then write the necessary data. Also, it's less likely to get fragmented if it never needs increasing in size.
I'm curious about the existence of swapfile.sys in that list though.
smakme7757
Golden Member
- Nov 20, 2010
- 1,487
- 1
- 81
Windows will almost always use the pagefile when it's available.
Windows memory management is extremely complicated. However a good read is the following article by Mark Russinovich at Microsoft
http://blogs.technet.com/b/markrussinovich/archive/2008/11/17/3155406.aspx
Windows memory management is extremely complicated. However a good read is the following article by Mark Russinovich at Microsoft
http://blogs.technet.com/b/markrussinovich/archive/2008/11/17/3155406.aspx
All windows will create and use a swap file. Besides, it also sets aside some space so that if the computer runs out of RAM, it has some space it can use which might not be available at a later time if the OS drive is full.
You can disable the swap file (in previous OS' you could, I have not played with windows 8 yet), but it is generally advisable not to. Espically as some programs I have come across over the years that will refuse to run/install if they do not detect a swap file that can have it's size increased.
You can disable the swap file (in previous OS' you could, I have not played with windows 8 yet), but it is generally advisable not to. Espically as some programs I have come across over the years that will refuse to run/install if they do not detect a swap file that can have it's size increased.
redzo
Senior member
- Nov 21, 2007
- 547
- 5
- 81
Thing to take into account regarding shrinking too much or completely disabling the page file: Make sure that the system never runs out of physical RAM. Unfortunately, even if you take a lot of precautions, a simple program error(like an application memory leak, for example) will mess things up for you.
I had to fine tune the paging file again after many many years. For compatibility reasons, is always better to leave it for the OS to manage its size. But ssd endurance concerns made me get back to the old and bad habit of altering the size of the pagefile. I don't take moving it on a mechanical hdd as a solution as this might negatively impact overall system performance(performance being one of the main benefits of OS's running on top of ssd's).
I had to fine tune the paging file again after many many years. For compatibility reasons, is always better to leave it for the OS to manage its size. But ssd endurance concerns made me get back to the old and bad habit of altering the size of the pagefile. I don't take moving it on a mechanical hdd as a solution as this might negatively impact overall system performance(performance being one of the main benefits of OS's running on top of ssd's).
Because I never use more then 12Gb of memory I set a 4GB ram pagefile with 1024mb on the os drive.
KingFatty
Diamond Member
- Dec 29, 2010
- 3,034
- 1
- 81
Manually set the pagefile to 500 megabytes (0.5 gigabytes).
You have 16 GB of RAM, so your computer will be unlikely to actually use the pagefile, but it is created by default. You could even delete it entirely, because you will be very very unlikely to run software that needs to use a pagefile in a computer that has 16 GB of ram.
I've set my pagefile to 0.25 GB and have never gotten an error. You can also enable a feature to allow the computer to enlarge/grow the pagefile if necessary. And your computer will likely never enlarge a tiny pagefile when you have so much ram.
You have 16 GB of RAM, so your computer will be unlikely to actually use the pagefile, but it is created by default. You could even delete it entirely, because you will be very very unlikely to run software that needs to use a pagefile in a computer that has 16 GB of ram.
I've set my pagefile to 0.25 GB and have never gotten an error. You can also enable a feature to allow the computer to enlarge/grow the pagefile if necessary. And your computer will likely never enlarge a tiny pagefile when you have so much ram.
BonzaiDuck
Lifer
- Jun 30, 2004
- 16,118
- 1,730
- 126
After observing the "Great Pagefile Discussions" for a while now, I've only made brief experiment of different pagefile configurations with my boot-system SSD thrown into the mix.
Consider "first thoughts" about how user-limited pagefile size affects (a) available disk space and (b) performance.
The first item depends on your hardware configuration choices: Did you actually spend money for 32GB of RAM, but choose to deploy an HDD (or even SSD) of only 100 GB? The question evaporates if you add additional disks for a range of storage functions, since the swapfile can be allocated among those disks.
I can easily afford a swapfile of default 16GB (given my RAM hardware) with the three ~500GB disks (2x SSD and 1x HDD) in my system. So the only reason I might fiddle with it manually would be any indication that actual performance significantly decreased under Windows own swapfile management.
I haven't seen anyone present any examples of degraded performance for using a Windows-determined swapfile size.
Consider "first thoughts" about how user-limited pagefile size affects (a) available disk space and (b) performance.
The first item depends on your hardware configuration choices: Did you actually spend money for 32GB of RAM, but choose to deploy an HDD (or even SSD) of only 100 GB? The question evaporates if you add additional disks for a range of storage functions, since the swapfile can be allocated among those disks.
I can easily afford a swapfile of default 16GB (given my RAM hardware) with the three ~500GB disks (2x SSD and 1x HDD) in my system. So the only reason I might fiddle with it manually would be any indication that actual performance significantly decreased under Windows own swapfile management.
I haven't seen anyone present any examples of degraded performance for using a Windows-determined swapfile size.
If your pc is set to sleep or is on 24/7 then a pagefile is nice to refresh your stale memory when needed.
Phynaz
Lifer
- Mar 13, 2006
- 10,140
- 819
- 126
VirtualLarry
No Lifer
- Aug 25, 2001
- 56,570
- 10,202
- 126
pagefile.sys AND swapfile.sys? On an NT-based box? Interesting.
At least on VMS, there was both a pagefile, and a swapfile. The idea being, that the pagefile was for virtual memory, for actively computing processes, and the swapfile, would hold processes that were swapped out in their entirety, because they were in a non-computable state (waiting on locks, I/O, etc.)
At least on VMS, there was both a pagefile, and a swapfile. The idea being, that the pagefile was for virtual memory, for actively computing processes, and the swapfile, would hold processes that were swapped out in their entirety, because they were in a non-computable state (waiting on locks, I/O, etc.)
KillerBee
Golden Member
- Jul 2, 2010
- 1,750
- 82
- 91
always store your page file on a ramdisk for quicker access 
Seriously for anyone who thinks you really need a page file no matter how much memory you have - or else it breaks something
Setting up a page file in a RAM disk when Windows starts with Imdisk:
http://forums.guru3d.com/showthread.php?t=356046
Will need their "swapadd" utility and use like this to create a 1GB drive to store the pagefile on the W: drive ramdisk:
imdisk -a -s 1G -m W: -p "/fs:ntfs /q /y"
swapadd W:\pagefile.sys 990M 990M
Seriously for anyone who thinks you really need a page file no matter how much memory you have - or else it breaks something
Setting up a page file in a RAM disk when Windows starts with Imdisk:
http://forums.guru3d.com/showthread.php?t=356046
Will need their "swapadd" utility and use like this to create a 1GB drive to store the pagefile on the W: drive ramdisk:
imdisk -a -s 1G -m W: -p "/fs:ntfs /q /y"
swapadd W:\pagefile.sys 990M 990M
Last edited:
Scarpozzi
Lifer
- Jun 13, 2000
- 26,391
- 1,780
- 126
I've got some Windows systems with 24-48GB of RAM....I've hard coded the size of the page files on those systems. It was eating into my file system too bad because the disks are SAS (smaller and more pricey than SATA).
They use an algorithm to set the size, but "They" aren't always right...that's why you can adjust it as needed. Change it, reboot, and if you see performance issues, change it again to something else.
I've read some people have totally disabled it when using virtualized environments, but that's to keep disk I/O from being subjected to un-needed chatter in large virtualized desktop environments (VDI/XenDesktop/etc). I've never bothered with ESX or Windows servers.
They use an algorithm to set the size, but "They" aren't always right...that's why you can adjust it as needed. Change it, reboot, and if you see performance issues, change it again to something else.
I've read some people have totally disabled it when using virtualized environments, but that's to keep disk I/O from being subjected to un-needed chatter in large virtualized desktop environments (VDI/XenDesktop/etc). I've never bothered with ESX or Windows servers.
The phrase "pants on head retarded" comes to mind. If you don't need a page file, putting one in RAM is exactly that - pants on head retarded.
KillerBee
Golden Member
- Jul 2, 2010
- 1,750
- 82
- 91
Read what? Even the author of the guru3d thread admits it's not a good idea.
Regardless, if you don't need a page file, why the hell would you stick one in RAM?
KillerBee
Golden Member
- Jul 2, 2010
- 1,750
- 82
- 91
Well the point is some people think you do need a page file to make certain apps work - no matter how much memory you have - I haven't experienced it myself though.
So for those who feel it is necessary to have at least some page file
here is a way to create a ramdisk on bootup and have the page file stored there.
Yes it sounds ridiculous but if you really really need to have a page file and have a lot of excess ram this may be better
So for those who feel it is necessary to have at least some page file
here is a way to create a ramdisk on bootup and have the page file stored there.
Yes it sounds ridiculous but if you really really need to have a page file and have a lot of excess ram this may be better
Last edited:
Yes, after reading the link you provided, wearing pants on my head seems relatively rational.
BonzaiDuck
Lifer
- Jun 30, 2004
- 16,118
- 1,730
- 126
Here's an explanation I quickly found which explains the subtle distinctions between "swapfile" and "pagefile" as noted by VirtualLarry.
http://www.techarp.com/showarticle.aspx?artno=143&pgno=1
Howsoever -- nobody answered my own question. "Does a Windows-managed [swap/page]file degrade your system performance?"
http://www.techarp.com/showarticle.aspx?artno=143&pgno=1
Howsoever -- nobody answered my own question. "Does a Windows-managed [swap/page]file degrade your system performance?"
TRENDING THREADS
-
Discussion Zen 5 Speculation (EPYC Turin and Strix Point/Granite Ridge - Ryzen 9000)- Started by DisEnchantment
- Replies: 24K
-
Discussion Intel Meteor, Arrow, Lunar & Panther Lakes Discussion Threads
- Started by Tigerick
- Replies: 19K
-
-
-
Facebook
Twitter