Ah, ok that changes everything. "mailboxes" ;) At 12:30 AM 11/11/04 +0100, Marcin Owsiany wrote: >> If u still need RAID 5 then I would make the stripe size equal to >> average file size / number of data disks up to no more than 32KB stripe. > >Since avg file size would be something around 2500 bytes, and we have 5 >disks, that would give us a 500 byte stripe. I don't think that is even >possible.
Since you (happy Adrian??) have lots of small essentially static files the limiting factor will probably be the disk I/O. Optimizing for I/O is a trade off for optimizing for non-wasteful disk usage. To bring down the number of I/O's needed to get a file u want to make the stripe larger. But making the stripe larger can slow down writes and waste space in the form of "latent space". If u have 32KB stripes so that almost every file fits in 1 stripe, the leftover space is wasted. So a 2.5KB file written in a 32 KB stripe wastes 30.5 KB. This could be ok if space is no object in the face of fast I/O speed. Given how cheap hard disks are now it could be worth it to err on the large side. The other caveat there is the read-recompute-write cycle of a large stripe. Smaller stripes speed this up. So all in all, for ur microscopic little files, I would make the stripe 4 KB. If ur having trouble with the stripe concept it is identical in practical use to a cluster on a normal partition. RAID:stripe::partition:cluster. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]