Just came in from Bugzilla ...
Subject: [Bug 121434] Extremely high iowait with 3Ware array and moderate disk activity https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=121434
------- Additional Comments From thomas.oulevey@elonex.ch 2005-07-29 08:55 EST ------- Hello, About the Linux 2.4 driver, we realized that we have big problem with the 9.2 driver. The 9.1.5.2 was fine. In fact the 9.2 firmware delivered (FE9X 2.06.00.009) with the driver is buggy if you use more than 1 unit. (Hotspares are considered as an unit.). We got a new firmware from 3ware support and it solves the problem. With some tweaking and 5 x RAID 5 volume on 3 x 3ware card (capacity around 5TB) we got with the iozone test 160MB/s write and 270MB/s Read. If you want more detailed information contact me.