Pagefile writes during large file operations on SSD

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I know SSDs are good enough now not to be too bothered about writes, however one thing bothers me.

I have 32GB RAM and most of the time the Pagefile isn't touched as free RAM is available.

However any kind of operation that fills the disk cache (eg large file copy operations) soon fills all 32GB (most of it just the windows disk cache) and Windows starts dumping huge writes to the pagefile. EDIT - writes are not as big as I thought but point still stands.

Is there a setting to tell windows to not dump ram to the pagefile just to make way for an even larger disk cache? I can understand to make way for memory for programs, but it seems wasteful just dumping RAM to SSD just because the disk cache has grown to 20GB using all free RAM.

Probably not, just thought I'd ask. Guess it will still last 10 years! :D
 
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Soldato
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if you are copying on a slow (hdd?) then unless you disabled disc caching for that, it is not unreasonable that it uses some of page file. ....

BUT are you saying when the copying is over things do not return to normal ? ie minimal disc actvity on pagefile ?
 
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Thanks for the replies, it does return to normal after heavy file reading/copying activity has finished - I just wondered if I could limit the disk cache size in RAM to say 10GB max using group policy or the registry. That means it doesn't start hitting the pagefile needlessly as free ram would still be available.

Did a search and it doesn't seem possible. It's fine, SDDs last ages and are cheap - I use an inexpensive one for pagefiles, scratch disks, temp etc and an expensive one as the main system disk.

I do a lot of heavy copying and working with large files and noticed Windows fills up all 32GB quickly then starts dumping RAM to the pagefile - even if the memory disk cache just contains info that only needs to read once during moving or copying. Just seems a waste of large writes on the SSD as the memory dumping is a few megabytes a second continuous writes until file operations stop.
 
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Unless you specifically do something that actually requires massive amounts of pagefile usage or other specific needs (where you'll probably already know what you need to set it to anyhow) then the best thing to do is set the pagefile to 1024MB minimum (this lets the OS work properly) and maximum to at least 8192MB - in most cases you won't need to set it higher but some users might need to set the max above 8192MB if they have a lot of heavy weight programs running simultaneously.

(Exception here being HDDs where you are best using a fixed size).

I don't recommend disabling it and setting it below ~700-800MB (so 1024 is a good point) can prevent the OS working properly in some "panic" situations where it can't adjust the pagefile before it needs to write. Leaving it on automatic or a fixed larger size doesn't actually accomplish anything other than put some additional writes on the SSD (not a big deal these days but still - due to the archaic way it is handled you tend to get a lot of block writes/flushes even when it needs to do small amounts) and take up storage space that probably will never be actually required by the pagefile in normal operation.

EDIT: Not 100% but if you've a lot of RAM (32+GB) and use hibernation features you might need to set max above 8192MB I've forgotten how that works now.

EDIT2: I've not really seen the behaviour you talk about though with file copying - nothing within the level I do gets anywhere close to maxing out available RAM and then moving to the pagefile.
 
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Thanks for the advice everyone - Rroff, it may be specific to the software I use then. Regardless, I really benefited from reading all you comments and will try a few suggestions out. :)
 
Soldato
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If you disable it, could be unknowingly impacting/limiting perforamce, if there is no cache when it could have been useful for slow IO.
 
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