Mark, On 6/12/06 7:16 PM, "mark@xxxxxxxxxxxxxx" <mark@xxxxxxxxxxxxxx> wrote: > I haven't. I'm meaning to take a look. Within registers, 64-bit should > be equal speed to 32-bit. Outside the registers, it would make sense > to only deal with the lower 32-bits where 32-bits is all that is > required. The short answer to all of this as shown in many lab tests by us and elsewhere (see prior post): - 64-bit pgsql on Opteron is generally faster than 32-bit, often by a large amount (20%-30%) on queries that perform sorting, aggregation, etc. It's generally not slower. - 64-bit pgsql on Xeon is generally slower than 32-bit by about 5% So if you have Opterons and you want the best performance, run in 64-bit. If you have Xeons, you would only run in 64-bit if you use more than 4GB of memory. - Luke
