On Mon, Jan 11, 2010 at 3:04 PM, Greg Smith <greg@xxxxxxxxxxxxxxx> wrote: > Scott Marlowe wrote: >> >> So, I took a break from writing and searched for some more info on the >> 74xx series CPUs, and from reading lots of articles, including this >> one: >> http://www.anandtech.com/cpuchipsets/intel/showdoc.aspx?i=3414 >> It seems apparent that the 74xx series if a great CPU, as long as >> you're not memory bound. >> > > This is why I regularly end up recommending people consider Intel's designs > here so often, the ones that use triple-channel DDR3, instead of any of the > AMD ones. It's extremely easy to end up with a memory-bound workload > nowadays, at which point all the CPU power in the world doesn't help you > anymore. The DDR3 Nehalem and DDR2 AMD are both actually pretty close in real world use on 4 or more socket machines. Most benchmarks on memory bandwidth give no huge advantage to either one or the other. They both max out at about 25GB/s. It's the older Xeon base 74xx chipsets without integrated memory controllers that seem to have such horrible bandwidth because they're not multi-channel. For dual socket the Nehalem is pretty much the king. By the time you get to 8 sockets AMD is still ahead. Just avoid anything older than nehalem or istanbul. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
