Wasn't the context switching issue occurring in specific cases only? I haven't seen any benchmarks for a 50% performance difference. Neither have I seen any benchmarks of pure disk IO performance of specific models of Dell vs HP or Sun Opterons.
Thanks, Anjan -----Original Message----- From: John A Meinel [mailto:[EMAIL PROTECTED] Sent: Monday, May 09, 2005 11:22 AM To: Anjan Dave Cc: Geoffrey; Mischa Sandberg; pgsql-performance@postgresql.org Subject: Re: [PERFORM] Whence the Opterons? Anjan Dave wrote: > You also want to consider any whitebox opteron system being on the > compatibility list of your storage vendor, as well as RedHat, etc. With > EMC you can file an RPQ via your sales contacts to get it approved, > though not sure how lengthy/painful that process might be, or if it's > gonna be worth it. > > Read the article devoted to the v40z on anandtech.com. > > I am also trying to get a quad-Opteron versus the latest quad-XEON from > Dell (6850), but it's hard to justify a difference between a 15K dell > versus a 30k v40z for a 5-8% performance gain (read the XEON Vs. Opteron > Database comparo on anandtech.com)... > > Thanks, > Anjan > 15k vs 30k is indeed a big difference. But also realize that Postgres has a specific benefit to Opterons versus Xeons. The context switching storm happens less on an Opteron for some reason. I would venture a much greater benefit than 5-8%, more like 10-50%. John =:-> ---------------------------(end of broadcast)--------------------------- TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]