Re: Allowing WAL fsync to be done via O_SYNC

* Tom Lane <tgl@sss.pgh.pa.us> [010318 14:55]:
> Alfred Perlstein <bright@wintelcom.net> writes:
> >> Just by making a thread call libc changes personality to use thread
> >> safe routines (I.E. add mutex locking).  Use one thread feature, get
> >> the whole set...which may not be that bad.
> 
> > Actually it can be pretty bad.  Locked bus cycles needed for mutex
> > operations are very, very expensive, not something you want to do
> > unless you really really need to do it.
> 
> It'd be interesting to try to get some numbers about the actual cost
> of using a thread-aware libc, on platforms where there's a difference.
> Shouldn't be that hard to build a postgres executable with the proper
> library and run some benchmarks ... anyone care to try?
I can get the code compiled, but don't have the skills to generate
a test case worthy of anything....

LER

> 
>             regards, tom lane
> 
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Larry Rosenman                     http://www.lerctr.org/~ler
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