Please help me tune FreeBSD for bulk.fefe.de/scalability/

[Devon H. O'Dell]

Felix von Leitner wrote:

>Hi!
>
>Several people have asked me to re-run my benchmarks after the kernels
>have been properly tuned.
>
Hey Felix,

To be totally fair, I'd like to point out the messages from 
freebsd-hackers that were sent earlier today:

On Fri, 24 Oct 2003, Michel TALON wrote:


>> What is more interesting is to look at the actual benchmark results in
>> http://bulk.fefe.de/scalability/
>> in particular the section about mmap benchmarks, the only one where
>> OpenBSD shines. However as soon as touching pages is benchmarked
>> OpenBSD fails very much.
>  
>

look closer.  openbsd's "touch page" times are identical to what you'd
expect a disk access to be.  the pages aren't cached, they're read from
disk.  so compared to systems that don't read from disk, it looks pretty
bad.  a 5 line patch to fix the benchmark so that the file actually is
cached on openbsd results in performance much in line with freebsd/linux.


The above is a reply by Ted Unangst; perhaps you'd like to look into this.

--Devon