Radoslav,

I exported about 100 3570s to DLT, and then imported the DLTs into LTO
after first stop at disk pool.  Total was about 1/2 TB.

My experience was that imports came in at about 3 MB/s despite the DLT
being capable of about 10 MB/s, the LTO of about 12 MB/s, and the disks of
about 14 MB/s.

Activity on the DB disks was low, so it wasn't a DB I/O issue.  Not sure
why the import performance is so slow, but it seems endemic to TSM.

System:
TSM 4.1 (.4.1 at the time if  I recall correctly)  on AIX 4.3.3 ML 8 on
7025 F50 with 2 x 332 MHz and 1 GB RAM.
Import from HP 4/40 DLT 8000 to disk pool volume which migrated to IBM
3583-L72 LTO.
All libraries HV diff SCSI.

Maybe the TSM developers can shed some light.

Tab Trepagnier
TSM Administrator
Laitram Corporation






Radoslav Bendik <bendik AT NS.HTC DOT SK>@VM.MARIST.EDU> on 04/24/2002 01:50:39 
AM

Please respond to "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>

Sent by:  "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>


To:   ADSM-L AT VM.MARIST DOT EDU
cc:
Subject:  LTO and backupsets, slow restore


Hello,

I have a problem with very slow restores from bakupsets from LTO tape
(200kB/s). Also import node runs very slowly (export node has generated
50G within 1 hour; less then 2G has been imported after 4 hours). Exports
and backupset generation is fast.

Is this normal behavior? Or there are some settings (tape block size,
buffer sizes), which can speed up restores? Problems are only on server
side.

Has anyone experiences with big export/import between TSM servers???


Environment is TSM server v4.2.1 on Solaris, LTO 3583 library connected
trough SAN. Clients are Solaris 7/8 on SAN.


--
rado b
rado b
        Why Did You Reboot That Machine?