Обсуждение: Re: [HACKERS] [COMMITTERS] pgsql-server/src/template bsdi

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Re: [HACKERS] [COMMITTERS] pgsql-server/src/template bsdi

От
Bruce Momjian
Дата:
Jan Wieck wrote:
> >> >My gcc 2.95.3 manual says:
> >> >
> >> >        -pipe  Use pipes rather than temporary files for  communi-
> >> >               cation  between  the various stages of compilation.
> >> >               This fails to work on some systems where the assem-
> >> >               bler cannot read from a pipe; but the GNU assembler
> >> >               has no trouble.
> >> >
> >> >so it looks like we can't use it on all platforms without testing.  I
> >> >will enable it for linux.  Do people want to test other platforms?
> >>
> >> It should work on any platform that uses the GNU tools, so that means
> >> *BSD is in the same boat as Linux.
> >>
> >> Does it really speed compilation though?  I saw somewhere that it
> >> didn't make much difference and might even hurt sometimes.
> >
> > I saw a 5 second improvement with -pipe on a 150 second full compile of
> > PostgreSQL.  However, I have a MFS /tmp.  I suppose if I didn't, it
> > would be slower.  However, the difference is so small as to be
> > meaningless.  Can someone else test on another *BSD and report?
> >
>
> Also, IIRC you have a dual processor box. In that case using -pipe helps
> to utilize 2 CPU's (not much though), whereas on a single CPU system it
> forces extra context switches that aren't necessary when running the
> stages sequential.

Oh, OK. I am on a dual, so maybe that's why I see an improvement.  If I
can get another BSD guy to test this, I can remove the pipe for all the
BSD's.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
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Re: [HACKERS] [COMMITTERS] pgsql-server/src/template bsdi

От
Sean Chittenden
Дата:
> Oh, OK. I am on a dual, so maybe that's why I see an improvement.
> If I can get another BSD guy to test this, I can remove the pipe for
> all the BSD's.

When benchmarking FreeBSD via worldstone, -pipe makes a difference
(how much remains a debate).  Since PostgreSQL's compile is small
enough, it's likely that many folks won't notice any appreciable
difference (though it does add up).  Here's a thread worth reading
from the gcc guys:

http://gcc.gnu.org/ml/gcc-bugs/2000-10/msg00138.html

-sc

--
Sean Chittenden