On Tue, 2002-04-02 at 14:33, James Cuff wrote: [...] > I guess my only question is whether anyone else used this type of software > RAID 0 on IDE in production farms before and are there any real gotchas, > tuning/tweaking or total nightmares I ought to be aware of? I have enough > nightmares, and would like to keep them to a minimum :-) On the tuning side, make sure your chunksize is set appropriately in /etc/raidtab The default value is not optimized for large block sequential reads (e.g. streaming databases from disk). Also, see if your chipsets support reliable UDMA/DMA operation. There are many other things you can do to optimize IO. Usually it is good practice to run vmstat 1 > log on a machine that you suspect of IO problems. This will give you a log snapshot of the high level system view. If you fill up your IO channel, or your disk is your limiting factor, you will be able to see it (with some practice/coaching) from this log. -- Joseph Landman, Ph.D. Senior Scientist, MSC Software High Performance Computing email : joe.landman@mscsoftware.com messaging : page_joe@mschpc.dtw.macsch.com Main office : +1 248 208 3312 Cell phone : +1 734 612 4615 Fax : +1 714 784 3774