Virtual RAM VS. Real RAM

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pentup

Limp Gawd
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Aug 12, 2002
Messages
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I learned alot from reading this thread, thanks guys. I know this thread is a bit old, sorry. I am about to reformat and I have a 2gig partition set aside on another drive that I plan to put a 512MB PF on. My question is this: What should I use for the allocation unit size? I don't plan on having anything else on there, just the paging file... I figured I should use something larger than the 'default' size in WinXP (how big is that, anyway?), but I'n not sure how high I should go.
 
err, i don't really understand your question, at all..

what do you mean by the "allocation size" ?? :confused:
 
when formatting with NTFS you can chose an allocation unit size, which im guessing is the same idea as cluster sizes in fat32. you can chose values ranging from 16-4096K.
 
Originally posted by pentup
when formatting with NTFS you can chose an allocation unit size, which im guessing is the same idea as cluster sizes in fat32. you can chose values ranging from 16-4096K.
Click to expand...

ah, so what you're asking is what your cluster [allocation unit] size should be for the partition your paging file will be put on?

short answer: idk.

long[er] answer: i don't know, i'm sorry. try PMing Ice Czar, the Moderator of the Storage (or w/e it's called :p) forum.
 
Originally posted by pentup
when formatting with NTFS you can chose an allocation unit size, which im guessing is the same idea as cluster sizes in fat32. you can chose values ranging from 16-4096K.
Click to expand...

I don't have any personal experience to back this up but I would suggest 512-1024 byte clusters. Anything bigger I think would be a waste of space overall when the pagefile is being accessed. Anything smaller than 512 could slow the system some due to the larger number of clusters that have to be accessed.

As I said, I have no real world experience messing with this and I have no site or anything to point you to to verify what I am saying. This is just my recommendation. You may not see any performance increase or decrease with any way you do it. I could just be getting mixed up while thinking about RAID 0 setups. I know the larger cluster arrays use up less CPU power generally while the smaller ones use up more but generally work faster if the CPU has no problem processing the RAID array. This is why "software" based arrays like those on many motherboards aren't all the great compared to a dedicated "hardware" RAID card.
 
I don't know, but it would make sense to me that you choose a large cluster/allocation unit size. From what I understand, the benefit of small clusters is basically that you don't waste harddrive space with small files taking up lots of space. On a swap partition, you will have one file, so there is no danger of small files taking up lots of space.

So I would guess that 4096k would be best. But again, I don't know.
 
Here is my basic understanding of cluster size optimization. The larger the cluster size the faster the access. However the larger cluster size means that every file is divided up into X number of chunks. So if you do 4k blocks and save a 1k file it takes up 4k worth of space. If it's a 21k file, it takes 24K. So the larger the file allocation size, the less 'stuff' you can fit on the drive.

So back to your case. You already know exactlly what is going on that volume, and you know the size. You would want a large allocation size for that useage. There may be some 'real world' reasons why you would want a smaller size, but nothing is jumping out at me. You may want to post this in Data Storage/Ice Czar suggestion is probably the best. Not only will he likely answer you Qs, he will link you to every word written about the subject. :D
 
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