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I have a workstation with 16GB of RAM, an 80GB boot SSD, and a software 4x 80GB array for scratch, running Windows 7 64-bit professional. The SSD is slower in sustained throughput than the array (especially on writes). It obviously seeks much faster. I generally use about half my RAM at any point. I've never seen it above 12GB usage.

This is only a question because space is at a premium on the SSD. I've shrank the pagefile to 2GB, but if possible, those 2GB would be nice to have back. Is moving the pagefile to the array going to be detremental to performance?

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  • Rule #1 of a solid-state drive: Never put a pagefile on it, or you're going to decrease the lifespan of the drive (given that said pagefile is used). Paging, even with a SSD, is still roughly 40 times slower than RAM. Get a mechanical hard drive for the pagefile to preserve the longevity of the SSD. Dec 13, 2011 at 17:28
  • @Breakthrough - Although the technical foundation is accurate, I think that's an unwarranted concern giving the average volume of writes involved in paging on most machines. I mean, Intel says you can write 21GB of data to their consumer-level drives every day for 10 years (!!!) without exhausting the write cycles.
    – Shinrai
    Dec 13, 2011 at 17:42
  • Now, that said, in this particular situation you have another perfectly serviceable location for it with better performance than a standard hard drive (that swap array) so I don't see any argument AGAINST moving it. I can't think that it would noticeably hurt performance, and it would remove potential load from the SSD. I just don't think there's any reason to be alarmed about having it on the SSD.
    – Shinrai
    Dec 13, 2011 at 17:45
  • @Shinrai: I agree people worry too much about write-cycles on modern SSDs. I mean, right now I'm defragging the thing (mostly for tail-packing purposes to reclaim more space -- 1.5GB and counting!) Dec 13, 2011 at 17:50
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    @Breakthrough: That myth needs to die already. Corsair blog put 240TiB of writes and deletes into a 60GB SSD before it died. That translates to 20GB of writes a day, for 33 years. That's on a small 60GB drive also. Larger drives will see a longer lifespan.
    – surfasb
    Dec 13, 2011 at 22:40

3 Answers 3

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Quite bluntly, I don't recommend doing any of that. Leave your page file alone. Let Windows run it. It does so better than you. If you are that skimped on space, get a larger drive. Don't jack with Windows management of the page file. It's just worth it.

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    I apologize.. I spoke to my senior admins to verify my answer and I was incorrect. It is apparently not a big deal to Move the SWAP file to another location. However both my seniors noted to Shrink it was indeed a horrible idea and to move it off the SSD despite your concerns not so good either. You want that on the fastest drive. Sorry for any bad info. Dec 13, 2011 at 17:38
  • Windows did a terrible job managing it, which is why I had to step in and do it myself. I leave it alone on mechanicals, but letting it take 24GB because "Windows knows more than me" is unacceptable on an 80GB drive. Dec 13, 2011 at 17:51
  • Also, what constitutes "fastest drive"? The array destroys the SSD on sustained throughput. Dec 13, 2011 at 17:55
  • There you have an excellent point. I have been discussing this with my mentors and really this is something that ideally you would already have some testing/knowledge of this. I didn't wanna keep spamming with comments or would have noted they also said your array isn't a "bad" choice although not usual. Dec 13, 2011 at 18:57
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    @insta That's assuming that the pagefile consists of reads and writes of "sustained throughput". While I'm speculating, I'm inclined to think that reading and writing 4kb pages to and from the pagefile is going to lead to a lot more random I/O rather than sustained I/O. Dec 14, 2011 at 0:11
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I would have said don't put your pagefile on the SSD, but this article at Microsoft suggests otherwise: Link

But if you've never used more than three quarters of your RAM, you probably don't really need a pagefile. Meaning that you should either move it to the normal hard drives (as it won't get used) or if you are feeling brave, remove the pagefile altogether.

Based on your comment on the other answer and on the MSDN blog post, I would say leave it alone* on the SSD!

  • Where leave it alone means constrain it to a sensible size (based on your other comments)!
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  • Of course, removing the pagefile has other consequences, since it isn't merely the lack of physical RAM that forces Windows to use the pagefile.
    – surfasb
    Dec 13, 2011 at 22:43
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Did you think about RAMDrive and swap-file on it? Swap on (even "modern") SSD is bad idea for SSD-life anyway

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  • The lifetime has been discussed in the comments in the OP. I'm already running a ramdrive for other purposes, but I'd rather let Windows have access to the RAM. If I was going to do that, I'd just disable the swapfile. Dec 13, 2011 at 23:20
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    Using a RamDrive for swap is one of the worst things you can do. Dec 14, 2011 at 0:11
  • @darth-android - really? And you can prove it with facts, otherwise you're just yap? Dec 14, 2011 at 17:26
  • Well, I don't exactly have scholarly articles on the subject, but it works out like this: "Free" memory isn't unused memory-- almost all of it is for disk cache and Window's SuperFetch. Memory management is always about keeping the most important data in memory, and forcing windows to keep that background process that runs once a week for 5 minutes in memory instead of caching the directory structure of My Documents (or something else used frequently), is bad. superuser.com/questions/314989 superuser.com/questions/315347 tinyurl.com/d6phqst Dec 14, 2011 at 19:34
  • serverfault.com/questions/23621 (Most appropriately, the highest-ranked answer specifically). If you'd like to discuss this further, we should take it to the Super User Chat Dec 14, 2011 at 19:40

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