On Sat, 26 Jun 2010 16:33:32 -0700 "jdow" <j...@earthlink.net> wrote:
> > Potentially. If you've got memory free for it, it certainly > > shouldn't perform worse. > > That might be a big if with a huge downside, Daryl. > > If the memory used by tmpfs forces SpamAssassin into memory swapping > any speed advantages are more than merely wiped out, aren't they? No, because, at worst, you are exchanging one type of disk access for another. A tmpfs partition is memory-backed by swap, a file on a normal filesystem is cached in memory. There's not all that much difference, they are both memory backed by a physical disk backing-store. A well designed kernel will place the physical memory where it's most effective, whether that's caching a file or keeping the tmpfs or process pages in ram. The advantage of tmpfs is not that it's stored in memory, it's that the kernel can put-off updating the backing store indefinitely - a temporary file can be created, updated and deleted without troubling the hard drive.
