ADSM-L

Re: Netware Backups (Length of Time)

1998-09-24 16:56:25
Subject: Re: Netware Backups (Length of Time)
From: Cindy Cannam <CCannam AT GENAM DOT COM>
Date: Thu, 24 Sep 1998 15:56:25 -0500
Jeff:

From my experience, Netware backups with ADSM are inherently slow, but they
don't have to be --- the best I've seen with small to medium file sizes has
been 4-5 GBs/hour, but most times, with exceptionally small files (50KBs or
less), the throughput really takes a dive. And we've recently compounded
our throughput headaches by a conversion to 100 Mb Ethernet from 16 Mb
Token Ring. The tuning from the network standpoint has been frustrating at
the very least, and this may be the place where you want to concentrate
some of your initial efforts if you've already exhausted ADSM's part in
your scenario. View the network from the client's NIC right out to the
backbone, into any router or switch, etc., and then into your server (you
didn't mention what server platform you're working with, but that would be
a concern as well). If your protocol parms are set according to your
environment's specifications (i.e., TCP/IP parms such as BUFFSIZE and
WINDOWSIZE), ADSM's part of the battle is half-way done.

Looking at items with your server activity during the Netware's backup
window also has a great deal to do with throughput --- the more activity
hitting your server and its database, the more likely things will slow down
to accommodate the load. How much activity is running on the network at the
same time as your backups? Do you have any copypool activity running during
this time-frame (I know from experience that this can have a dramatic
effect on server CPU activity and availability for other process
time-slices, even on a mainframe ADSM server).

And watch your DB cache hits as well --- if you're consistantly seeing
numbers below 98%, your parms aren't set correctly for your environment.

Hope this gives you a starting point.

C.L.Cannam
Storage Management
GENAM/St. Louis, MO/USA
ccannam AT genam DOT com




"Bruns, Jeff" <Bruns.Jeff AT PRINCIPAL DOT COM> on 09/24/98 10:50:05 AM

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

To:   ADSM-L AT VM.MARIST DOT EDU
cc:    (bcc: Cindy Cannam)
Subject:  NetWare Backups (Length of Time)




Hello all, we have been having a problem with our NetWare 4.11 backups
taking a tremendous amount of time to perform their nightly incrementals
10 hours in some cases.

The amount of changed data does not seem to be the issue.  It appears
more to be how ADSM processes each file to determine if it should be
backed up or not.  Our actual throughput for the files that are actually
backed up is acceptable.  But the more objects it needs to inspect, the
longer the job runs.  Here are results of one of our servers:

09/24/1998 07:41:33 --- SCHEDULEREC OBJECT END NETWARE_PRIORITY
09/23/1998 22:00:00
09/24/1998 07:41:33 --- SCHEDULEREC STATUS BEGIN NETWARE_PRIORITY
09/23/1998 22:00:00
09/24/1998 07:41:33 Total number of objects inspected:  709,879
09/24/1998 07:41:33 Total number of objects backed up:    9,088
09/24/1998 07:41:33 Total number of objects updated:          0
09/24/1998 07:41:33 Total number of objects rebound:          0
09/24/1998 07:41:33 Total number of objects deleted:        394
09/24/1998 07:41:33 Total number of objects failed:          17
09/24/1998 07:41:33 Total number of bytes transferred:   269.16 MB
09/24/1998 07:41:33 Data transfer time:                  158.81 sec
09/24/1998 07:41:33 Network data transfer rate:        1,735.58 KB/sec
09/24/1998 07:41:33 Aggregate data transfer rate:          7.91 KB/sec
09/24/1998 07:41:33 Objects compressed by:                    0%
09/24/1998 07:41:33 Elapsed processing time:           09:40:36
09/24/1998 07:41:33 --- SCHEDULEREC STATUS END NETWARE_PRIORITY
09/23/1998 22:00:00

If you look at it from the aspect that it almost 10 hours to back up
only 270MB, you can understand the concerns I have.

We are running the V3R1L1.3 client for Netare and the as far as I know
the latest release for our ADSM server.  My knowledge is limited to the
client side.

If my assumptions are accurate in that the problem is how it processes
each and every file - are there any tunable parameters or anything else
I can do to try to speed things up.  As it is, our backups are running
into our morning login times.

Any help would be greatly appreciated.

Jeff Bruns
Netware Research/Support
Principal Financial Group
Des Moines, Iowa
515-248-8631
<Prev in Thread] Current Thread [Next in Thread>