On Tue, 2006-09-05 at 00:42 +0400, Roman Krylov wrote: > Hi. > My config: > gentoo linux "2005.1" on amd64x2 in 64-bit mode, > kernel 2.6.16.12 > glibc 3.3.5(NPTL), > gcc 3.4.3. > I had not used portage for building. > I built two versions of postgres from sources: > postgresql-8.1.4 native(64bit) > and 32-bit with CFLAGS=... -m32, and "LD = > /usr/x86_64-pc-linux-gnu/bin/ld -melf_i386" in src/Makefile.global. > 32-bit build runs much faster than 64 apparently. > What benchmark utility should I run to provide more concrete info (numbers)? > What could be the reason of that difference in performance? > I am also interested in 32-bit versus 64-bit performance. If I only have 4GB of RAM, does it make sense to compile postgresql as a 64-bit executable? I assume there's no reason for PostgreSQL's shared buffers, etc., to add up to more than 2GB on a system with 4GB of RAM. Is there a general consensus on the matter, or is it highly application- dependent? I am not doing any huge amount of 64-bit arithmetic. I am using Woodcrest, not Opteron. Regards, Jeff Davis
