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de><ta
04-14-09, 09:30 AM
I am thinking about using the following 16GB SSD dedicated solely for the pagefile.
http://www.newegg.com/Product/Product.aspx?Item=N82E16820609330

Since the pagefile for vista is less then 1MB for each page, I am guessing the SSD's read times should help out performance a lot.

I am not going to have a page file on the main HD (happens to be a velociraptor). Opinions?

Bman212121
04-14-09, 10:12 AM
That's definitely a tough one. I'm not so sure you'll see a big increase in performance mainly because the pagefile only holds data after it has already been read from the drive. The other concern is that some of the cheaper SSD controllers have issues with random writes.

In a sense just buying 8GB of ram and turning off the swap file completely should have a larger impact than getting an SSD. I have done that in the past but I can't say as I have noticed a difference, so I'm guessing you'll have the same results with an SSD.

de><ta
04-14-09, 11:00 AM
If Vista page faults then the write to the swap / page location is not of much concern. Since the way it operates is as it reads from the main hd, into memory it also writes back to the page file (it gets done in parallel).

The performance increase I am thinking about is when it finds a file / block in the swap, the seek time + read time from a SSD would be a lot smaller then the seek time + read time from a normal HD. Also most of the paged file blocks are about 512KB to a 1MB in size.

walterman
04-14-09, 12:50 PM
What about disabling the swap & buying more ram ?

de><ta
04-14-09, 01:20 PM
What about disabling the swap & buying more ram ?

Problem with that approach is once anything gets loaded onto RAM it stays on it until it get unloaded.

The objective of the swap file is to:
1) provide the illusion you have more memory
2) cache regularly used files and provide a faster start up

wolfgar
04-14-09, 02:22 PM
I don't think thats a good use. SSD's have a limited number of write times per memory block of approx 10,000 erase/writes each block (note: a block is similar to a HDD sector). Software in the SSD spreads out the wear, but it adds up over time.

I just read a review on the intel x-25 (specifically the new driver) and he specifically mentioned that he would use it for boot and high performance read heavy volumes because of the increased performace VS HDD's, but would avoid using it for continuous small write style usage and specifically mentioned the Cache being elsewhere.


Right now the price/performance is just not there.

I vote for the 'Add RAM' and reduce your swapping usage.

|MaguS|
04-14-09, 02:25 PM
What about disabling the swap & buying more ram ?

Problem is some programs might become unstable. I know Photoshop complained when I use to disable my pagefile.

Sazar
04-14-09, 03:28 PM
Honestly Dex, it's not a bad idea.

But I am thinking that the overall performance gain vice the cost would make this a poor investment currently :)

Bman212121
04-14-09, 03:29 PM
Problem with that approach is once anything gets loaded onto RAM it stays on it until it get unloaded.

The objective of the swap file is to:
1) provide the illusion you have more memory
2) cache regularly used files and provide a faster start up

I'm not so sure that the pagefile does this. I know windows uses .pf (prefetch) files for starting the pc, but I'm not as sure that it will know to read the pagefile to look for files after the pc has been rebooted.

de><ta
04-14-09, 03:56 PM
I'm not so sure that the pagefile does this. I know windows uses .pf (prefetch) files for starting the pc, but I'm not as sure that it will know to read the pagefile to look for files after the pc has been rebooted.

You are correct with regards to the the prefetch files (.pf) , but I believe the virtual memory / swap portion gets refilled every time the system restarts.

I will experiment around with it and see if I can get any benchmarks in terms of performance. Hopefully I get all my parts by tomorrow and I can start building my system.

walterman
04-14-09, 04:17 PM
Problem with that approach is once anything gets loaded onto RAM it stays on it until it get unloaded.

The objective of the swap file is to:
1) provide the illusion you have more memory
2) cache regularly used files and provide a faster start up

Don't want to start a discussion about this, but the virtual memory (page file) is used to swap memory pages between 2 levels of the memory hierarchy (ram/disc).

... but I believe the virtual memory / swap portion gets refilled every time the system restarts.

Yes, this is correct.

...I will experiment around with it and see if I can get any benchmarks in terms of performance...

The first time that you load a program in memory, the system might spend some time swapping memory pages between the ram/hdd (if there are no free memory pages in the ram).

Problem is some programs might become unstable. I know Photoshop complained when I use to disable my pagefile.

Photoshop is very memory hungry. Try to lower the percentage of physical ram that PS will use (preferences menu). PS has its own memory manager. I'm using it a lot for my textures projects, and i'm running 4GB on a 32bit OS. Also, try to set the PS swap file into another drive. :)

And returning to the original subject of the thread, my point is that if you add more ram to the system, your system will swap less memory pages between the ram/disc. Also, if you know what you are doing, you can turn off the page file, and your system will run without the extra overhead of the pagefile disc swap.