Re: New to PostgreSQL, performance considerations

* Cosimo Streppone:

> "-O0" ~ 957 tps
> "-O1 -mcpu=pentium4 -mtune=pentium4" ~ 1186 tps
> "-O2 -mcpu=pentium4 -mtune=pentium4" ~ 1229 tps
> "-O3 -mcpu=pentium4 -mtune=pentium4" ~ 1257 tps
> "-O6 -mcpu=pentium4 -mtune=pentium4" ~ 1254 tps

-mcpu and -mtune are synonymous.  You really should -march here (but
the result is non-generic code).  Keep in mind that GCC does not
contain an instruction scheduler for the Pentium 4s.  I also believe
that the GCC switches are not fine-grained enough to cover the various
Pentium 4 variants.  For instance, some chips don't like the CMOV
instruction at all, but others can process it with decent speed.

--
Florian Weimer                <fweimer@bfk.de>
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