Re: [PERFORM] Hardware/OS recommendations for large databases (

[Luke Lonergan]

Dave, From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Dave Cramer Sent: Tuesday, November 15, 2005 6:15 AM To: Luke Lonergan Cc: Adam Weisberg; pgsql-performance@postgresql.org Subject: Re: [PERFORM] Hardware/OS recommendations for large databases ( Luke, Have you tried the areca cards, they are slightly faster yet.  No, I've been curious since I read an earlier posting here.  I've had a lot more experience with the 3Ware cards, mostly good, and they've been doing a lot of volume with Rackable/Yahoo which gives me some more confidence.   The new 3Ware 9550SX cards use a PowerPC for checksumming, so their write performance is now up to par with the best cards I believe.  We find that you still need to set Linux readahead to at least 8MB (blockdev --setra) to get maximum read performance on them, is that your experience with the Arecas?  We get about 260MB/s read on 8 drives in RAID5 without the readahead tuning and about 400MB/s with it.   - Luke