Howdy, all.

I've done a decent amount of small-scale online restores from my
offsite virtual volumes, and never been particularly unhappy with the
speed.  (though come to think of it I've never timed it either)

But I'm restoring a pretty big volume now, and it's taking a L-O-N-G
time.  I was hoping to elicit war stories from some of you, and see if
my expectations are just out of whack.


Environment: Everything is TSM 5.5.3 on AIX.  I've got about 350 miles
between primary and secondary site.


I regularly get 80 MB/s sustained running tape to tape from primary to
offsite over this link.  I've got plenty of TCP buffer space, and I've
set my TCP windows to be 2M on all the servers.

When I use iperf to check just TCP/IP throughput, I get 800-900Mb
avg. over 30 seconds, with sustained 1Gb plateaus.  So the network
level seems reasonable.

But the restore is rattling around in the vicinity of 2.5 MB/s; just
incredibly slow.

Now, these are small files; average is just 300K, and most of them are
much smaller (email messages).  But the database on the restoring
server isn't thrashing, I don't find any bottlenecks at first look.


So.  What have you-all seen out of your restores?  I really need to
characterise this; It would Not Be Good if this were the best I could
do in a real emergency.


- Allen S. Rout