Re: mysql scaling questions

Bruce Evans wrote:

FreeBSD has more layers, with less optimization in each layer. Normally
this doesn't matter, since everyone knows that syscalls are expensive
and avoids them :-).

My point is that the majority of applications are written for Linux and
they are both syscall-intensive and faster there, so maybe something can
be done in FreeBSD.

No Pipe-based Context Switching? That should be included in benchmarks to
show FreeBSD slowness :-), since it is affected by both slow syscalls and
slow context switches.

Unfortunately, I found out this one on my own application.

Um, execl and process creation are not syscall-intensive. They take about
1 syscall each.

Yes, in what amounts to a tight loop. They don't try to measure syscalls
directly but I'd say they are intensive.

Linux wins this benchmark by a lot mainly because too much weight is given
to the file copy benchmarks

In this particular instance I don't care about file system performance
(and I believe that unixbench's benchmarks are outdated in this way and
measure more of the file system cache than they should). Though it would
be nice to have a FreeBSD file system that doesn't suck :)

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