Josh, The 6650 can have upto 32GB of RAM.
There are 5 drives. In future, they will be replaced by a fiber array - hopefully. I read an article that suggests you 'start' with 25% of memory for shared_buffers. Sort memory was suggested to be at 2-4%. Here's the link: http://www.ca.postgresql.org/docs/momjian/hw_performance/node8.html Maybe, I misinterpreted it. I read the document on http://www.varlena.com/varlena/GeneralBits/Tidbits/perf.html and the suggested values are much lower than what I have mentioned here. It won't hurt to start with lower numbers and increase lateron if needed. Thanks, Anjan -----Original Message----- From: Josh Berkus [mailto:[EMAIL PROTECTED] Sent: Tuesday, October 21, 2003 12:21 PM To: Anjan Dave; [EMAIL PROTECTED] Subject: Re: [PERFORM] Tuning for mid-size server Anjan, > Pretty soon, a PowerEdge 6650 with 4 x 2Ghz XEONs, and 8GB Memory, > with internal drives on RAID5 will be delivered. Postgres will be from > RH8.0. How many drives? RAID5 sucks for heavy read-write databases, unless you have 5+ drives. Or a large battery-backed cache. Also, last I checked, you can't address 8GB of RAM without a 64-bit processor. Since when are the Xeons 64-bit? > Shared_buffers (25% of RAM / 8KB)) = 8589934592 * .25 / 8192 = 262144 That's too high. Cut it in half at least. Probably down to 5% of available RAM. > Sort_mem (4% of RAM / 1KB) = 335544. We'll take about half of that - > 167772 Fine if you're running a few-user-large-operation database. If this is a webserver, you want a much, much lower value. > Effective_cache_size = 262144 (same as shared_buffers - 25%) Much too low. Where did you get these calculations, anyway? > In a generic sense, these are recommended values I found in some > documents. Where? We need to contact the author of the "documents" and tell them to correct things. > joins, orderby, groupby clauses. The web application is based on > Apache/Resin and hotspot JVM 1.4.0. You'll need to estimate the memory consumed by Java & Apache to have realistic figures to work with. > Are the above settings ok to begin with? Are there any other > parameters that I should configure now, or monitor lateron? No, they're not. See: http://www.varlena.com/varlena/GeneralBits/Tidbits/perf.html to tune these parameters. -- Josh Berkus Aglio Database Solutions San Francisco ---------------------------(end of broadcast)--------------------------- TIP 9: the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match