Re: Linux v.s. Mac OS-X Performance
Douglas McNaught <doug@mcnaught.org>
From: Douglas McNaught <doug@mcnaught.org>
To: "Scott Marlowe" <scott.marlowe@gmail.com>
Cc: "Sam Mason" <sam@samason.me.uk>, pgsql-general@postgresql.org
Date: 2007-11-12T17:50:21Z
Lists: pgsql-general
"Scott Marlowe" <scott.marlowe@gmail.com> writes: > On Nov 12, 2007 11:37 AM, Sam Mason <sam@samason.me.uk> wrote: >> And what's the performance hit of using native 64bit code? I'd guess >> similar, moving twice as much data around with each pointer has got to >> affect things. > > That's not been my experience. It's not like everything you do > requires 64 bits to be moved where in 32 bit code only 32 were moved. > The performance gain of the 64 bit machine doing 64 bit operations > over the 32 bit machine doing them (i.e. floating point etc...) is so > much more that it more than makes up for the overhead of running in 64 > bit mode. Plus, 64-bit mode gives you twice as many CPU registers, which is a huge win for some algorithms, though in many cases it doesn't make much of a difference. -Doug