PageFile, 8+GB Ram, SSD Speed etc...

[ksec]

Yes i know M$ told us not to disable Pagefile because it is suppose to be part of the memory system. But that advice was given when the world was still stuck at 2GB and 4GB of Mid - High Class System. Nowadays you could easily go to 16GB Ram for High End and it doesn't cost an Arm and Leg. A further Node Shrink would properly bring us to 16GB and 32GB Memory world.

Pagefile off would force everything to be cached inside RAM. Especailly with SuperCache in Vista and 7.

With more things cached inside RAM, your usage pattern would likely have a lot less Random Read Write and and more Seq Read Write. As we have seen in previous Anand article, Seq Read Write is actually MUCH more important then we think.

If Anand's SSD test were done with a 4x4GB RAM and PageFile Turned off, we may be see much less gains from Sandforce 2200, and especially on test with non compressible data.

I already tweeted Anand but no reply ><.

Anyone else interested?

 

[Emulex]

you know that windows doesn't compress the pagefile and hiberfil like osx?

 

[Voo]

Pagefile off would force everything to be cached inside RAM. Especailly with SuperCache in Vista and 7.

With more things cached inside RAM

Since Win7 (umn and vista too I think) already uses the complete RAM (minus a few mb here and there) to cache data, what makes you think that disabling the pagefile - and therefore not allowing the scheduler to replace dirty pages it thinks won't be used in the next time with more sensible data (and it's not as if it were shuffling gb of data around here; also those are low priority IOs) - will make much or any difference at all?

That would only be reasonable if the win7 scheduler was provably bad, which seems unlikely, but you can always try to convince us 🙂

 

[ksec]

Since Win7 (umn and vista too I think) already uses the complete RAM (minus a few mb here and there) to cache data, what makes you think that disabling the pagefile - and therefore not allowing the scheduler to replace dirty pages it thinks won't be used in the next time with more sensible data (and it's not as if it were shuffling gb of data around here; also those are low priority IOs) - will make much or any difference at all?

That would only be reasonable if the win7 scheduler was provably bad, which seems unlikely, but you can always try to convince us 🙂

Yes, But even if you uses complete RAM, have 30 Tabs of Data in Firefox ( 2GB Total Memory ) + All Windows Services, DLL, Loaded, you are still only reaching 4.5GB RAM. That is 3.5GB of Ram that Windows cant even fill up even when it try its best.

 

[Voo]

Yes, But even if you uses complete RAM, have 30 Tabs of Data in Firefox ( 2GB Total Memory ) + All Windows Services, DLL, Loaded, you are still only reaching 4.5GB RAM. That is 3.5GB of Ram that Windows cant even fill up even when it try its best.

That's strange - for my machines windows always uses all of the available RAM for caching.

Maybe a quick glance in %WINDIR%/Prefetch/Layout.ini could show if somethings amiss? There shouldn't be any shortage of files to prefetch.

 

[Phynaz]

The weekly person that thinks they know more about memory management than Microsoft.

 

[Bauss]

The weekly person that thinks they know more about memory management than Microsoft.

lawl. This.

To the OP: I'm not sure what you'd expect to find from that kind of test. SSDs are so much more capable of dealing with random reads and writes while doing other things that the odd page out during a test will not have any measurable impact.

Disabling the pagefile was a trick from a few years back when RAM was abundant, yet hard drive access latency was still tens of thousands of times slower than RAM was. That's not the case anymore.

 

[Nothinman]

Yes i know M$ told us not to disable Pagefile because it is suppose to be part of the memory system. But that advice was given when the world was still stuck at 2GB and 4GB of Mid - High Class System. Nowadays you could easily go to 16GB Ram for High End and it doesn't cost an Arm and Leg. A further Node Shrink would properly bring us to 16GB and 32GB Memory world.

And on an AMD64 system each process gets 16TB, or 44 bits worth or virtual address space. So your 16G or 32G of memory isn't anywhere near being able to accommodate even what 1 process could attempt to allocate. Obviously no process is going to try and actually use all 16TB right now, but it could use several gigs loading a large video, image, game, etc and you've gone and removed Windows' ability to push older, unused pages to the pagefile in order free up memory for that allocation.

Since no thread is complete without a car analogy...

Essentially you're removing your seatbelts and airbags in order to make your car go a little bit faster; the net win is virtually zero but the risk is a lot higher.

And you may want to get a new keyboard, yours appears to randomly type a dollar sign when you hit the 's' key...

 

[groberts101]

I've been running without a pagefile for years even when using HDD. If your usage never bumps into the pagefile.. what's the big deal?

If a page file was so critical then everyone would see SSD like performance by running out and buying 24 gigs of ram. So, if your usage doesn't tax the amount you already have?.. you will be wasting money for no perceivable gain. Just remember here, just because Windows "CAN" use it all doesn't mean it will.

So in essence, we can't run out and buy more ram to get that seat of the pants improvement that we used to on older systems running 512MB's and it's silly to think that most would really see gain or loss one way or the other here. Unless of course you were too cheap to order that system with at least 2 gigs of ram. In which case, moving to 4 gigs might make a slight difference during heavy multitasking. Slight being the keyword there. lol

and to further the use of car analogies.. it would be like putting racing tires on a car that only goes 80MPH and wondering why it won't go any faster.

 

[bradley]

Windows warns the user when memory is running low to shut down programs. The safe strategy has been to maintain the pagefile at a smaller static size.

With 16GB I am able to disable the pagefile entirely without issue, save SSD wear-and-tear. Though Linux has it most right; you can set the pagefile to only be used when necessary.

 

[groberts101]

yep. It's also been said that Windows 7 has the ability to auto-grow the pagefiles size to compensate. Comes from a very reliable Windows beta tester source but I don't speak from experience there, so not positive about that one.

EDIT: maybe it was the ability to initialize/create one even when one has not been set? can't remember now.

 

[Nothinman]

yep. It's also been said that Windows 7 has the ability to auto-grow the pagefiles size to compensate. Comes from a very reliable Windows beta tester source but I don't speak from experience there, so not positive about that one.

Windows has always had that ability, but it respects the upper limit set so once you hit that it'll just start failing memory allocation requests and causing apps to crash since virtually none handle those gracefully. However, Windows can't (not sure about Win7) shrink the pagefile at runtime so once it grows it won't reset back to the minimum size until you reboot.

 

[groberts101]

Hmm.. learning all sorts of new things around here today. Thanks for the reply.

 

[hanspeter]

And on an AMD64 system each process gets 16TB, or 44 bits worth or virtual address space. So your 16G or 32G of memory isn't anywhere near being able to accommodate even what 1 process could attempt to allocate.

But eight of those terabytes are shared among all processes 🙂

 

[ksec]

And on an AMD64 system each process gets 16TB, or 44 bits worth or virtual address space. So your 16G or 32G of memory isn't anywhere near being able to accommodate even what 1 process could attempt to allocate. Obviously no process is going to try and actually use all 16TB right now, but it could use several gigs loading a large video, image, game, etc and you've gone and removed Windows' ability to push older, unused pages to the pagefile in order free up memory for that allocation.

Since no thread is complete without a car analogy...

Essentially you're removing your seatbelts and airbags in order to make your car go a little bit faster; the net win is virtually zero but the risk is a lot higher.

And you may want to get a new keyboard, yours appears to randomly type a dollar sign when you hit the 's' key...

I am running on Systems, and in fact MANY systems will have total memory ( Pagefile + RAM ) less then 8GB. Since Windows Vista or 7, Windows will no longer scale more then double your RAM as Pagefile if you have 2GB or Higher. Previously Windows allocate as much as 2.5 times of your RAM as Pagefile. But Having 5GB as pagefile is just silly.

And if a program ever have to allocate 16GB of things there is obviously something wrong. At least that is on the desktop side of things.

 

[Nothinman]

I am running on Systems, and in fact MANY systems will have total memory ( Pagefile + RAM ) less then 8GB. Since Windows Vista or 7, Windows will no longer scale more then double your RAM as Pagefile if you have 2GB or Higher. Previously Windows allocate as much as 2.5 times of your RAM as Pagefile. But Having 5GB as pagefile is just silly.

And if a program ever have to allocate 16GB of things there is obviously something wrong. At least that is on the desktop side of things.

My work Win7 laptop has it set to system managed and it's currently at 8G which is 1x my system memory so Windows doesn't default to 2.5x anymore either. Not that I'm advocating either size because there's no one size that fits all workloads, I'm just saying that disabling it completely is really stupid.