>>>>> "Daniel" == Daniel Kasak <[EMAIL PROTECTED]> writes:
Daniel> There is NO speed difference between 32 and 64 bit on AMD processors. Sorry, but that is not true. In long mode there are twice as many general purpose registers and twice as many vector registers. The ABI used by Linux and the BSDs -- and I would have to presume Solaris as well -- takes advantage of the extra registers and does result in faster execution for most (compiled) code. There is extra pressure on the cache due to the larger size of pointers and longs -- which is what causes 64 bit code to run slower on cpus like the Power, MIPS and SPARC families -- but that is more than offset by the improved ABI. Daniel> The main difference for database use is that 64 bit processors Daniel> can address MUCH more memory, so your DB software doesn't have Daniel> to do nasty tricks ( that slow things down ) to deal with large Daniel> databases. The above said, that is indeed the real reason to prefer 64 bit for the database manager process even on processors like the UltraSPARC. Also, the schema in the dbmail sources makes heavy use of the INT8 data type. PG handles those much better on an -m64 compile than on a -m32 compile. The speed increase I got when I converted my personal mail store to use INT4 everywhere INT8 is currently specified -- except for the dbmail_users table; my curmail_size is greater than 2 Gigs -- was significant. And I cut my disk space usage by about half. Definitely compile postgresql with -m64. If you are on amd64 also compile dbmail with -m64. On UltraSPARC you may find dbmail will run faster compiled with -m32, but given how much use it makes of int64_t I'd give both versions a test. -JimC -- James Cloos <[EMAIL PROTECTED]> OpenPGP: 1024D/ED7DAEA6 _______________________________________________ DBmail mailing list [email protected] https://mailman.fastxs.nl/mailman/listinfo/dbmail
