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Is Video RAM a Good Swap Device?
sean4u writes "I use a 'lucky' (inexplicably still working) headless desktop PC to serve pages for a low-volume e-commerce site. I came across a gentoo-wiki.com page and this linuxnews.pl page that suggested the interesting possibility of using the Video RAM of the built-in video adapter as a swap device or RAM disk. The instructions worked a treat, but I'm curious as to how good a substitute this can be for swap space on disk. In my (amateurish) test, hdparm -t tells me the Video RAM block device is 3 times slower than the aging disk I currently use. If you've used this technique, what performance do you get? Is the poor performance report from hdparm a feature of the hardware, or the Memory Technology Device driver? What do you use to measure swap performance?"
This doesn't sound like the most stable thing to do especially if your running a server on the same computer. It sounds good on paper but implementing it is a whole different game. From my years in IT never try anything like this on production servers, thats what test servers are for.
Which is, of course, a completely useless and disingenuous answer to a person who already has the graphics memory sitting around, and wants to know if it is better than a hard drive.
You seem to be advocating wasting perfectly good VRAM in favor of buying more system RAM. If the VRAM is essentially free (ie. comes with the system no matter what), there is no good reason not to try to put it to good use.
Also, your "No" is completely unqualified. You offer no details of how VRAM performs worse as swap space than hard drives, let alone actual benchmarks or citations. (And I have the feeling that most graphics memory would be significantly better than your average IDE hard drive for swapping.)
Mod parent overrated.