Hi all,

We are running ADSM 3.1 on a R40 (6 way 200MHz) hi node in an SP2.  We are
backup up
a 1TB DB2 EEE database which is running on 24 silver nodes (2 way 332 MHz).
The SP2
is running at AIX 4.3.2 and PSSP 2.4.  The ADSM server has a 3494 attached
with 16
3590 B1A tape drives.

Our problem is that, we started out with 6 drives and completed the backup
in 12 hours.
Now that  we added 10 drives and 2 additional frames to the 3494, our
backup is actually
taking longer to complete 13-14 hours using 8 drives at a time.  The DB2
backups write directly
to tape. I am hoping to complete the backups within 9 hours or less using
up to 12 drives.

I have started playing around with the tuning values in ADSM and AIX, but
have not come up
with the correct combination. So, if anyone has any experience with a
similar setup, any help
is appreciated.

Here are our tuning settings:

SP switch settings on all nodes:
     spoolsize/rpoolsize      16777216  (16MB)
AIX
     thewall             262144
     sb_max              1310720
     tcp_sendspace       655360
     tcp_recvspace       655360
ADSM Server
     MoveBatchSize  1000
     MoveSizeThresh           500
     TxnGroupMax              256
     UseLargeBuffers          Yes
     TCPBufsize               16384
     TCPWindowsize            0
     TCPNoDelay               Yes
ADSM Client
     TCPBuffsize         32
     TCPWindowsize       640
     txnbyte                  25600
     tcpnodelay               Y
     uselargebuffers     yes



Thanks for the help.  Alex