On 10/02/2011 05:25 PM, Tom Lane wrote:
Andrew Dunstan<and...@dunslane.net> writes:I have been investigating some build performance issues, and trying to narrow down causes of slowness, and observed an odd effect, which was suggested by a huge time difference between building from git and building from a tarball. If I do make -C src/port all and then wait 10 seconds or so and do make -j 3 or even just plain make the build finishes much much faster (like 1m vs 5m) than if I had not run the first command.Can't reproduce that here. What I do notice on a Fedora 14 machine is that ccache seems to be enabled by default, ie you get caching even when you just say "gcc", and that makes a huge difference in build times. I see 70 seconds after "rm -rf ~/.ccache", versus 4 seconds with it fully populated. Building src/port first saves nothing in either starting state. I wonder whether your experiments got affected by something similar.
Yes, possibly, although SL6 (which is an RHEL clone) doesn't have ccache by default. I'm not sure what happened there, as now I can't reproduce it either.
Sorry for the noise. cheers andrew -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
