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Old 02-22-2007, 12:44 PM
Mastertech Mastertech is offline
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You have absolutely no idea what you are talking about:

Putting a Paging File in a RAM drive is a ridiculous idea in theory, and almost always a performance hit when tested under real-world workloads. You can't do this unless you have plenty of RAM and if you have plenty of RAM, you aren't hitting your paging file very often in the first place! Conversely, if you don't have plenty of RAM, dedicating some of it to a RAM drive will only increase your page fault rate. Now you might say "yeah, but those additional page faults will go faster than they otherwise would because they're satisfied in RAM." True, but it is still better to not incur them in the first place. And, you will also be increasing the page faults that have to be resolved to exe's and dll's, and the paging file in RAM won't do diddly to speed those up. But thanks to the paging file in RAM, you'll have more of them. Also: the system is ALREADY caching pages in memory. Pages lost from working sets are not written out to disk immediately (or at all if they weren't modified), and even after being written out to disk, are not assigned to another process immediately. They're kept on the modified and standby page lists, respectively. The memory access behavior of most apps being what it is, you tend to access the same sets of pages over time... so if you access a page you lost from your working set recently, odds are its contents are still in memory, on one of those lists. So you don't have to go to disk for it. Committing RAM to a RAMdisk and putting a paging file on it makes fewer pages available for those lists, making that mechanism much less effective. And even for those page faults resolved to the RAMdisk paging file, you are still having to go through the disk drivers. You don't have to for page faults resolved on the standby or modified lists. Putting a paging file on a RAMdisk is a self-evidently absurd idea in theory, and actual measurement proves it to be a terrible idea in practice. Forget about it.
Flash memory on the HD ("i-RAM) or Flash memory drives have nothing to do with a RAMdisk. Taking away system RAM for a RAMdisk is couter productive and will reduce performance. Windows Vista takes advantage of Flash memory devices to further improve performance via ReadyBoost but there is no RAMdisk in system RAM and the paging file is NOT disabled.

Telling someone to disable the paging file is even more absurd. I suggest you read up on how the paging file works. Please STOP spreading completely inaccurate misinformation.

XP Myths

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