Mehdi Salehi wrote:
> Hi,
> Which one performs better in TSM for AIX:
> 1- using one big TSM volume on a big striped filesystem
> 2- using multiple smaller TSM volumes each on a separate filesystem (each
> filesystem resides on a separate hdisk)
> (in either case, disks are RAID protected in disk subsystem layer)
>
> I assumed that TSM does not lock a volume while a client is sending backup
> data to it such that other clients can read/write from/to this volume
> simultaneously. Correct me if I am mistaken, please.

My experience on Linux is that having multiple, separate RAID groups is
better than having one giant RAID group. You get better reliability
since you have more failure groups, and better performance since you
spread your disk contention out more.

I can't find the source to back it up, but I think even for
random-access DISK volumes only one client can be doing I/O at a time to
any given volume. This means that creating multiple DISK volumes per
RAID group will give better performance.

--
-- Skylar Thompson (skylar2 AT u.washington DOT edu)
-- Genome Sciences Department, System Administrator
-- Foege Building S048, (206)-685-7354
-- University of Washington School of Medicine