Re: Swap

["Daniel R. Killoran,Ph.D." <drkilloran@speakeasy.net>]

On Mar 17, 2005, at 4:48 AM, Michael wrote:

> How crucial is a swap partition?

It is not crucial for it to be a separate partition. Apple, for 
instance, does not, by default - they use space on the boot disk 
instead.
However - if you don't, and if the partition you share with something 
else begins to become full or excessively fragmented, VERY strange 
things start to happen! Users frequently had this experience using the 
early versions of OS-X (partially because hard disks provided were much 
smaller then).

This is common to ALL versions of Unix, as far as I know.

Personally, I have ALWAYS used a separate partition, and I was 
gratified to find that I never encountered any of the strange problems 
reported by people who left OS-X in its default configuration.

As to the question of whether you need a swap partition at all, given 
that you have a lot of memory, obviously you could use a RAM disk for 
the purpose. Whether it would be faster is problematical. I seem to 
remember somebody tried it - on NetBSD I think - and it didn't speed 
things up noticably.

There are many versions of Unix that have an "embedded" configuration, 
in which there is often no disk drive. I don't know whether they use a 
RAM disk or just do without.

Dan Killoran