Re: Optimization levels when compiling PostgreSQL...

Sean Chittenden writes:

> Hrm, I should go check the archives, but I thought what was used was
> one step below -C[fF] and was used because of size concerns for
> embedded databases.  My memory for what happens on mailing lists seems
> to be fading though so I'll look it up.

The particular decision was -CF vs. -CFa ("a" for alignment).  The latter
was about 2% faster in the test case but increased the size of the
executable by 80 kB.

Note that the test case was extremely contrived -- parsing of about 70 MB
of uninteresting commands with little to no other activity.  For a normal
command the scanner overhead is really small.

On the other hand, the test case was run on a x86 machine which is not
known for being sensitive to alignment.  So on a different architecture
you might get more significant speedups.  Try it if you like.

-- 
Peter Eisentraut   peter_e@gmx.net