Re: performance hit with --enable-debug

> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> >> The effect in terms of query execution speed is probably minimal.  The
> >> problem is that the executables get about 15% larger, which can lead to
> >> longer load times, more memory usage, and ultimately to some speed issues.
>
> > Not sure about the longer load times.
>
> I don't believe that either.  The debug symbol tables aren't part of the
> memory-resident image, they just sit out there on disk ... at least in
> Unixen that I'm familiar with.
>
> I think this is worth looking at more closely.  I can't see any reason
> that Tom should be seeing a 30x performance hit from --enable-debug;
> there's something going on here that I don't understand.

I believe Peter was discussing image size, which while it affects the
binary size, it sits at the end of the binary and never gets loaded from
disk.

I believe debug adds some addition checks in the code, and that is why
he is seeing slowness with debug.  It was not the -g flag he used but
--enable-debug.  I just looked at configure.in, and saw the
--enable-debug enables assert checking.


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