Re: OSDL DBT-2 w/ PostgreSQL 7.3.4 and 7.4beta5

On Sat, Nov 01, 2003 at 02:37:21PM +0100, Manfred Spraul wrote:
> Tom Lane wrote:
>
> >markw(at)osdl(dot)org writes:
> >
> >
> >>7.4beta5 offers more throughput. One significant difference I see is in
> >>the oprofile for the database. For the additional 7% increase in the
> >>metric, there are about 32% less ticks in SearchCatCache.
> >>
> >>
> >
> >Hmm. I have been profiling PG for some years now, and I cannot remember
> >ever seeing a profile in which SearchCatCache topped everything else
> >(the usual suspects for me are palloc/pfree support code). Can you give
> >any explanation why it looks like that? Can your profiling code tell
> >where the hotspot call sites of SearchCatCache are?
> >
> If I understand the docs correctly, op_to_source -a can do that - the
> result is annotated assembly, with percentage numbers for each
> instruction. If the sources were compiled with -g2, even source level
> annotation is possible.
>
> Mark, do you still have the oprofile output? I don't understand why so
> much time is spent in the kernel signal handlers, i.e. I could use
> annotated assembly or source of linux/kernel/signal.c.

I haven't been saving the raw output, but I will start. I'll try to get
some annotated source for the kernel going too.

Mark