Re: Hardware/OS recommendations for large databases (

["Luke Lonergan" <LLonergan@xxxxxxxxxxxxx>]

Dave,

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From: pgsql-performance-owner@xxxxxxxxxxxxxx [mailto:pgsql-performance-owner@xxxxxxxxxxxxxx] On Behalf Of Dave Cramer
Sent: Tuesday, November 15, 2005 6:15 AM
To: Luke Lonergan
Cc: Adam Weisberg; pgsql-performance@xxxxxxxxxxxxxx
Subject: Re: 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