From: Allan Ballard (aballard_at_ix.netcom.com)
Date: Thu Aug 05 1999 - 18:50:23 EDT
Isn't that a risky venture? If 'dose locks or crashes,
wouldn't instructions in the ramdisk be lost?
On Thu, 5 Aug 1999 11:01:08 -0700, Michael Geary wrote:
>For anyone who is experimenting with putting a Windows swapfile on a RAMdisk,
don't bother. There is no benefit at all in doing
>this, only a loss of performance and available memory.
>
>The swapfile is not a special thing that Windows needs to have and enjoys using. It is
merely a slower substitute for memory,
>nothing more or less. If your Windows applications are using more memory than is
physically available, Windows can use part of the
>disk as if it were memory. To do this, it swaps pages in and out between physical
memory and the disk. By doing this swapping, the
>operating system lets programs run as if there were more memory available than is
physically in the machine.
>
>Suppose you manage to create a 32Mb RAMdisk in which you'll place your swapfile.
By doing that, you've reduced the available
>physical memory in your machine by 32Mb. Therefore, Windows will need to start
swapping 32Mb sooner than it would have otherwise.
>You've gained absolutely nothing, you've lost some performance, and you won't
even get back the whole 32Mb in swap space because of
>file system overhead.
>
>If you have enough memory in your machine that you'd like to eliminate swapping to
disk, simply use the system control panel to turn
>off virtual memory completely. This will eliminate disk swapping, at the cost of limiting
your memory use to what's physically
>available in the machine. This is the exact same benefit you'd hope to gain by putting
the swapfile in a RAMdisk, except you
>eliminate all the software overhead. You just use memory as memory.
>
>If your machine currently does swap to disk with the set of applications you use, that
means you're using more memory than the
>machine actually has. If you eliminate swapping, you'll also reduce the number and
size of applications you can load.
>
>But if you'd loaded that smaller number of applications in the first place, you wouldn't
be swapping anyway. Turning off swapping
>just prevents you from loading more apps than fit in memory.
>
>-Mike
>
>ThinkPads in the Open Directory: http://geary.com/thinkpad/
>
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