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270

TL;DR version: Let Windows handle your memory/pagefile settings. The people at MS have spent a lot more hours thinking about these issues than most of us sysadmins. Many people seem to assume that Windows pushes data into the pagefile on demand. EG: something wants a lot of memory, and there is not enough RAM to fill the need, so Windows begins madly ...


64

Eric Lippert recently wrote a blog entry describing how Windows manages memory. In short, the Windows memory model can be thought of as a disk store where RAM acts as a performance-enhancing cache.


40

As I see from other answers I am the only one that disabled page file and never regreted it. Great :-) Both at home and work I have Vista 64-bit with 8 GB of RAM. Both have page file disabled. At work it's nothing unusal for me to have few instances of Visual Studio 2008, Virtual PC with Windows XP, 2 instances of SQL Server and Internet Explorer 8 with a ...


31

You may want to do some measurement to understand how your own system is using memory before making pagefile adjustments. Or (if you still want to make adjustments), before and after said adjustments. Perfmon is the tool for this; not Task Manager. A key counter is Memory - Pages Input/sec. This will specifically graph hard page faults, the ones where a ...


27

I've run my 8GB Vista x64 box without a pagefile for years, without any problems. Problems did arise when I really used my memory! Three weeks ago, I began editing really large image files (~2GB) in Photoshop. One editing session ate up all my memory. Problem: I was not able to save my work since PS needs more memory to save the file! And since it was PS ...


18

While the answers here covered the topic quite well, I will still recommend this read: http://blogs.technet.com/markrussinovich/archive/2008/11/17/3155406.aspx He talks about PF size almost at the end: Some feel having no paging file results in better performance, but in general, having a paging file means Windows can write pages on the modified list ...


14

"Pages Input / sec is the counter to watch, but you shouldn't worry about it "swapping" as windows does not use the page file like *nixes do. First you need to understand that windows pages in not out. I'm going to quote the relevent portion of Eric Lipperts blog post (lightly edited) since I can't say it any better myself: "RAM can be seen as merely a ...


12

The best answer I can think of is that under a normal load you may not use up the 8GB, but it is the unexpected loads where you will run into trouble. With a page file, the system will at least run slowly once it starting hitting the page. But if you remove the pagefile it will just die (from what I know). Also 8GB seems like a lot now, but a few years ...


11

Actually it doesn't make a lot of difference as long as you don't use sparse files. Creating a "normal" file with dd will allocate the file (if at all possible) in a single run, while creating a sparse file will tell you that you have a 10GB file lying around but not actually using up all the space. I'm not quite sure wether mkswap won't allocate the space ...


11

The traditional answer would be to separate the pagefile from the System drive but the X-25E's performance should generally make that unnecessary, especially on a server. If you can't put enough RAM in the system to avoid unnecessary paging, or you have applications (like Exchange 2007) that can make quite a lot of use of paging no matter what, then putting ...


11

Windows memory management relies heavily on the paging file(s) for many reasons, not only for "swapping out" in low memory conditions; this has been the subject of endless debates, but the bottom line is: Windows actually works a lot better when there's a page file, even if plenty of RAM is available. You should leave it on, unless you're severely limited ...


10

The SD card would be classed as a removable device, which would explain why it's not usable to hold the page file (removing the SD would mean a bunch of memory space just disappeared from underneath the kernel -- and (most*) kernels generally don't like that much). You might get some use out of the SD card as a ReadyBoost device, assuming you can convince ...


9

This doesn't make much sense. Also, by moving the pagefile off of the boot volume, you lose the ability for the OS to dump crash info in the event of a BSOD. This makes troubleshooting a pain. On top of that, I can't imagine that your performance would increase by any meaningful amount. Just leave it where it is. If you're paging a lot, solve the actual ...


7

On hard disks, throughput and seeking is often faster towards the beginning of the disk, because that data is stored closer to the outer area of the disk, which has more sectors per cylinder. Thus, creating the swap at the beginning of the disk might improve performance. For a 2.6 Linux kernel, there is no performance difference between a swap partition and ...


6

Near the end of this article, Mark Russinovich briefly discusses system-managed pagefile sizes: You’ll notice that the default configuration is for Windows to automatically manage the page file size. When that option is set on Windows XP and Server 2003, Windows creates a single paging file that’s minimum size is 1.5 times RAM if RAM is ...


6

The 1.5 times physical RAM is just a guideline. There are some general pointers about page file sizing in this Technet article which makes the point: On server systems, a common objective is to have enough RAM so that there is never a shortage and the pagefile is essentially, not used. On these systems, having a really large pagefile may serve ...


5

Checkout http://blogs.msdn.com/e7/archive/2009/05/05/support-and-q-a-for-solid-state-drives-and.aspx However, the below might apply more to consumer usage, than server usage, so take it with a grain of salt. Should the pagefile be placed on SSDs? Yes. Most pagefile operations are small random reads or larger sequential writes, both of which are types ...


5

There is no performance gain at all in putting your pagefile on a different partition on the system disk. There is a gain, instead, in putting it on a different physical disk, but only if there are no other workloads on it. Edit To address your comment: Compression is a Very Bad Idea for a page file, as it needs to be accessed precisely at random ...


5

It does exactly what it says on the tin: the OS manages the size of the pagefile, which can shrink or grow dynamically, and with no lower or upper bounds. The pro is that you don't have to worry about sizing your pagefile, the con is that your pagefile can become fragmented. Where it is useful is in exactly the situation it's designed to avoid: sizing your ...


5

You didn't mention if it's a 64-bit edition of Windows, but I guess yes. The pagefile serves many things, including generating a memory dump in case of BSoD (Blue Screen of Death). If you don't have a pagefile, Windows won't be able to page out to disk if there isn't enough memory. You may think that with 8 GB you won't reach that limit. But you may have ...


5

I'm not a virtualization expert (in fact I think it's the wrong tool for the job most times), but from what I have read your guest OS's should not be allowed to swap. The primary reason for preventing swapping is it represents a way for one guess OS to hog a large portion of th e host's IO bandwidth. Also, you don't want to pretend to your guess OS's that ...


4

The only person that can tell you if your servers or workstations "need" a pagefile is you, with careful use of performance monitor or whatever it's called these days. What apps are you running, what use are they seeing, what's the highest possible memory use you could potentially see? Is stability worth possibly compromising for the sake of saving a minute ...


4

Disabled my page file (8GB x86 laptop) and had two problems even with 2500MB free. 1) ASP.NET error trying to activate WCF service : Memory gates checking failed because the free memory (399556608 bytes) is less than 5% of total memory. As a result, the service will not be available for incoming requests. To resolve this, either reduce the load on the ...


4

You're on a Windows OS that is 10 years old. If you can, move to a 64-bit platform and/or fix the application/driver/whatever that is causing it. Have you identified what it is? If not, here's some help on that score. If not, you're just trying to deal with the situation as-is. You can set it; it might not be able to be set much higher than you've already ...


4

Yes, the paging deltas would give you a live indication of how much the server is paging (or "swapping"), but only at that moment. To watch this more closely, and to see a historical view, I would suggest using Performance Monitor (perfmon.exe) to chart or record those deltas (and any other performance counters of interest that may help to correlate ...


3

You need to understand how windows memory works. My answer here give you that information. If you don't care about memory dumps when windows crashes you can reduce the pagefile to your normal working set.


3

Why would you do that? Memory is cheaper - just buy more memory? Anyway, if you insist then so long as your PCIe SSD acts as an AHCI device then it will be available at boot time and could be selected as a swap drive yes - some don't let you do this, basically if it lets you boot from it you'll be fine, if you need drivers then you may very well not be able ...


3

No. I can't think of any technical reason why there would be a downside to moving the pagefile location to another drive of sufficient size in your situation. In fact we do this for all of our servers to improve deduplication rates. Additionally, I have found that if you are running up against disk space limitations that WinDirStat is useful in identifying ...


3

I think at the stage we're at now, unless you're running a laptop with a configuration that writes the data to the swap when it suspends/sleeps, swap should really be considered "last resort". Your best bet is to put enough RAM in a box so that it never pages to disk. That being said, a partition is probably the better way, performance wise, though a file ...


3

That would heavily depend on the consequences of overcommitting memory on your host OS. I would be a bit more than annoyed if, for example, I'd have the Linux out-of-memory killer slay my virtual machine. I tend to set aside a smaller, separate, preallocated, snapshot-independent (if applicable to your VM solution) virtual disk for each guest OS, ensure the ...



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