Hello, we full backup our 22.3 GB DB (assigned, used 92%) 
in 39 minutes, using Magstar 3590E cartridges in the 3494 robotic.
Th DB is laying on mirrowed ssa-disks (7133) using 18GB-disks (ibm7133-8518) 
Processor in RS600/H50, OS/AIX 4.3.3 , TSM4.1.3.0

...mabe you should first check the capability of the disks where your db
is located - what you would get there by reading on unix for example 
a simple test would be done using dd for example 
( if you have your server on unix) 
Example:
# time dd if=/some_data_located_on_the_db_disk of=/dev/null bs=1024k count=100
100+0 records in.
100+0 records out.

real    0m8.396s
user    0m0.010s
sys     0m1.890s
# 
... would get the time to just read 100MB ( just at the time of the test )
running the example -dd- test again can to unrealistic low times when 
running the example -dd- test again can to unrealistic low times when 
data is cached, so a new test should be done with new data ( if=...)


> > -----Original Message-----
> > From: Zoltan Forray/AC/VCU [SMTP:zforray AT VCU DOT EDU]
> > Sent: Wednesday, June 27, 2001 3:37 PM
> > To:   ADSM-L AT VM.MARIST DOT EDU
> > Subject:      Database backup performance
> >
> > Any suggestions on how to improve DB backup performance ?
> >
> > Doing a FULL DB backup of our 15GB ADSM (yes, not TSM YET. Hoping to
> > convert to 4.1.3 RSN !!) server, sometimes takes 4-hours.
> >
> > Since I read a previous message about someone having a 52GB DB, I was
> > wondering how long it takes to backup that much DB since my meager DB
> > takes
> > sooooo long ? Note, there is no "operator delay" since it goes to a 3494
> > ATL, using 3490E drives. I was thinking about moving it to 3590 MAGSTAR
> > but
> > wasn't sure if it would make much of a difference since the only real
> > change would be reduction/elimination of tape mounts (currently uses
> > 9-cartridges). Since it is a robot, this would save a few minutes at most.
> >
> > I have tried increasing the BUFPOOL value (from 32MB to 80MB) with little
> > noticable improvement. I still haven't reached/sustained the illusive 98%
> > Cache Utilization !
> >
> > Since the ADSM address space working set size has often exceed 110MB, I
> > was
> > wondering what was reasonable (or expected) for thise size DB. How much
> > further should I increase the BUFPOOL value ?
> >
> > ===========================
> > Zoltan Forray
> > Virginia Commonwealth University
> > University Computing Center
> > e-mail: zforray AT vcu DOT edu
> > voice: 804-828-4807

-- 
Mit freundlichen Grüßen / best regards
Mit freundlichen Grüßen / best regards
Rainer Wolf


 __________________________________________________________
                                                           
 Rainer Wolf                  rainer.wolf AT rz.uni-ulm DOT de  
 Tel: 0731-50-22482           Fax: 0731-50-22471           
 University of Ulm            http://www.uni-ulm.de/urz                    
 University Computing Center  Albert-Einstein-Allee 11   
 AG Basissysteme              89069 Ulm