Page file management for best performance

[tempoct]

Which one has best real world performance. Says all on a single RAID 0 volume.
1. OS and page file on same partition
2. Page file is in different partition than OS.
3. Page file is in different and dedicated partition (sized just little bigger than needed size)

General rules (AFAIK) is page file should be set with static size (for the recommended size, which usually 1.5 x Physical Memory size).

Wonder which one has best performance in real world. If the performance doesn't differ much, choice 1 is the best for simplicity.

What do you think? This is for XP 32 and Vista 64. OS shouldn't be much different though.

 

[BobSutan]

You might as well add one more option for the poll:

4. Page file on different disk than OS

 

[XOR != OR]

You might as well add one more option for the poll:

4. Page file on different disk than OS

Or

5. Page file on different controller. Which would yield the best results, if only marginally.

 

[Hamfiles]

Please read Micorosoft's article here.

http://support.microsoft.com/kb/197379

According to the article, when muliple page files are set up, and one of them is on a drive separate from the drive the OS is on, "Windows uses an internal algorithm to determine which page file to use for virtual memory management.....The page file on the less frequently used partition will be used the majority of the time because it is not on a busy partition".

IMO, it is worth it to make a page file on a separate drive, if you are running 2 hard drives. Also, it is best to make the page file size a fixed size, so that it does not get fragmented.

 

[MChief]

Page on a disk other than the one you load your most apps (including the os) from. I keep mine on my media array and my OS/Games, etc on their own array.

On linux systems I generally use swap partitions, on winders I find that there is little need to create a dedicated partition for the swap file.

On linux I usually mirror the swap partitions and activate the /dev/mdX device.

 

[bbz_Ghost]

Of the choices available, the first - same as the OS partition meaning just leave it alone and let Windows handle it - is the best performance option.

The only time you may or may not notice any benefits and increased performance is if you can put the pagefile on a secondary drive that is on its own entirely seperate controller and not use that drive/controller for most anything else - this is relatively impractical in the long run because it literally says "Ok, this is my pagefile drive and nothing else."

With IDE drives which are still really popular, the problem comes from the fact that two drives hooked up to the same controller cannot be accessed at the same time. You can't read from the Primary Master and write to the Primary Slave at the same time. If you were doing a file copy from PM to PS on the same controller, a chunk of data is read from the PM then sent to the PS and the cycle repeats. It's not "copy on the fly" which is obviously much better if it's possible.

SATA drives should not suffer that same issue because they work a bit differently, but... well...

In my experience, which I won't get into again since I toot my own horn too often as it is, seriously...

Install Windows, and just leave it alone.

I've done more tweaks, more installs, more reinstalls, more retweaks, more builds, edits, configurations, nLite stripped installs, vLite Vista stripped installs, etc... You end up getting drowned in being concerned about performance that typically only shows itself in a benchmark that is designed to not only look for such a difference but present hard data about it also.

I ended up having to get to a point where I said, "Ok, I spend entirely too much time eeking out another .5% performance improvement..."

After that time, I just installed Windows, whatever version, and you know what... it works fine. It's fast enough for me (Core 2 Duo 1.66 with 2GB of RAM these days, laptop), and I have a lifetime of knowledge to share with others if they choose to go that "Tweak Addict" route.

Just my $.02... Happy Holidays

 

[Gatticus]

I agree, some people are far too concerned with tweaking. I've tried the pagefile in every possible configuration and never noticed any performance benefit over just letting windows handle it on the same partition as the OS. Maybe there is a minute measurable performance difference by putting it on a second HDD on it's own controller but in real world usage you will never notice that difference.

 

[djnes]

I agree, some people are far too concerned with tweaking. I've tried the pagefile in every possible configuration and never noticed any performance benefit over just letting windows handle it on the same partition as the OS. Maybe there is a minute measurable performance difference by putting it on a second HDD on it's own controller but in real world usage you will never notice that difference.

Maybe it's a trend for the new year, but I agree with you. The only "tweak" I've ever seen yield any results is setting a static size, which cuts down on disk fragmentation. I do believe I've read something that states putting the page file on a separate partition on the same disk could actually lower performance, but again, probably not in a very discernable way.

Also, the 1.5 x RAM rule isn't really in effect anymore. I have 2 GB of memory, and there's no way I need 3 GB of virtual memory. I have mine set at a static 1024 MB, on my C partition.

 

[tempoct]

Thanks everyone. Good discussion.

 

[dbaldus]

Page on a disk other than the one you load your most apps (including the os) from. I keep mine on my media array and my OS/Games, etc on their own array.

On linux systems I generally use swap partitions, on winders I find that there is little need to create a dedicated partition for the swap file.

On linux I usually mirror the swap partitions and activate the /dev/mdX device.

Would you still recommend that I have the page file set up on my secondary hard drive, even though that hard drive is a Sata I 7200.7 and my OS hard drive is a Sata II 7200.9? I have a dedicated 2 Gb partition on my older, slower drive for the page file (the rest is all storage)... but is the performance actually going to be worse since it is on a much slower drive?

 

[bbz_Ghost]

Just posted a reply about this in another thread where you just asked the same question. Go find it...

The biggest issue that slows down pagefile usage is: the hard drive can't do two things at once, PERIOD. That's it, that's the final absolute 100% only thing that matters.

When the OS needs to page data out of chip RAM to the hard drive, or when it needs to page data back into chip RAM, getting access to that pagefile is where computer performance suffers the worst possible hit because as we all know, a mechanical device like a hard drive will never be anywhere as fast as solid-state chip RAM is.

So, if you set yourself (meaning your system) up in such a way that you increase the efficiency with which the OS can access the pagefile whenever it needs to, you increase performance. The simplest way to do this is with at least two physical hard drives each attached to its own controller (IDE drives would mean one drive per cable, not both on the same cable; SATA and SCSI don't suffer this issue) and a pagefile on each drive.

This allows the OS to access either of them as necessary, i.e. if the OS needs to read data into RAM from drive 1, it can then page data out of RAM to make room for the incoming data to the pagefile on drive 2, almost in real-time - obviously it's not real-time, but it's way way faster than this:

Write a chunk of data from RAM to drive 1's pagefile; read a chunk of data into RAM to replace it; repeat the process till the necessary data is in RAM and the unnecessary data (idle) was swapped/paged to the pagefile for safe keeping.

Compare that with this:

Write a chunk of data from RAM to drive 2's pagefile while simultaneously reading a chunk of data into RAM from drive 1.

Far more efficient, and much faster in operation, and over the course of thousands upon thousands of such reads and writes, things are faster overall.

This all becomes a moot issue most of the time since it's only noticeable in specific benchmarks that can test for such things, and those are big ones like SYSMark05 or whatever. Simple drive speed testing benchmarks can't provide the answers or results most people want, and SYSMark05 is ridiculously expensive for no good damned reason.

But again, for most people, just letting Windows handle it works best for most if not all situations. It is possible to improve pagefile performance, it just becomes a hassle of not only doing it but being able to prove the effort was beneficial in the first place.

 

[Josh_B]

Page on a disk other than the one you load your most apps (including the os) from. I keep mine on my media array and my OS/Games, etc on their own array.

On linux systems I generally use swap partitions, on winders I find that there is little need to create a dedicated partition for the swap file.

On linux I usually mirror the swap partitions and activate the /dev/mdX device.

RAID 0 for the swap, RAID1 for the rest.