Re: Hardware/OS recommendations for large databases (

Dave,

________________________________

From: pgsql-performance-owner(at)postgresql(dot)org
[mailto:pgsql-performance-owner(at)postgresql(dot)org] On Behalf Of Dave Cramer
Sent: Tuesday, November 15, 2005 6:15 AM
To: Luke Lonergan
Cc: Adam Weisberg; pgsql-performance(at)postgresql(dot)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