On 20/02/06, Hannah Schroeter <[EMAIL PROTECTED]> wrote: > Hello! > > On Mon, Feb 20, 2006 at 01:17:05PM +0000, Constantine A. Murenin wrote: > >[...] > > >Yes, there is always some compromise. But in this specific case we > >have much less than even a fifth of memory actually being used for > >programmes and kernel etc. Some of the rest is used for cache, but it > >still stops at around 3/4 or even 4/5 of the memory being wasted for > >nothing. > > >We are not dealing here with a case of someone wanting to use the > >remaining 64MB for disc cache on a 2GB server (assuming the rest of > >memory being already utilised for cache): -- this is a case of a 512MB > >machine behaving as if it was a 128MB one, not using the extra 3/4 of > >available memory. I assume that even if I put the extra 1G in, the > >proportion of wasted memory will only increase. > > If this is a common state of affairs, you can always raise the > percentage of memory used for the buffer cache in the kernel, using > config -e: config -e -o /bsd.new /bsd > then the command > cachepct [number] Show/change BUFCACHEPERCENT > helps. The default is 5, you could raise it to 10 or even more.
Thanks, I think this is indeed an option I was looking for (however, it looks like I was looking for it in the wrong place -- `sysctl kern` tree). Although the documentation says that it defaults to 5%, it actually seems to default to 10% on amd64, alpha, hppa and hppa64. Why it's not made to default to 10% on i386 too if enough memory is available? Also, it looks like "Filesystem Buffer" was in the FAQ in 2003-05-01 (http://www.se.openbsd.org/faq/faq11.html), stating "option BUFCACHEPERCENT=30" for config(8), but now it no longer appears in today's version (http://www.openbsd.org/faq/faq11.html). Is there a reason for that? > >And 512MB, I must add, is the de facto minimum today for any machine, > >making this even lack of tune-up even more unacceptable. > > OpenBSD doesn't run only on i386/amd64, remember this. And until > recently, my home machine still had 96 MB RAM. True, I was making a generalisation to mean any modern PC/mac. :-) It was almost a year ago that 512MB became the minimum even for most entry models. Cheers, Constantine.
