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

Tom Lane wrote:

>markw@osdl.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.

--   Manfred