Thanks for the reply Bill,
I'm testing with only 1 filesystem. My intent is to be able to initiate
multiple sessions
(threads) reading a single filesystem and interleave the data on to two tapes
much the same was as
Veritas does. Testing shows that regardless of TCPIP or SHRDMEM as the
commmethod, I am able to get
multiple sessions operative with inconsistent results.
Using SHRDMEM, resour 3, maxnummp 4 , 1 session is my admin session and the
other two participate in
the backup until one of them decides to formally end. The remaining session
keeps running like the
energizer bunny although much slower.
Using TCPIP, resour 3, maxnummp 4, the session act as before except none of them
formally ended. Thinking theres an issue with SHRDMEM, I cancelled the two
active sessions, changed resour from 3 to 9 (hoping 4 sessions (threads) would
be
allocated to tape1 and 4 sessions (threads) would be allocated to tape 2... the
remaining session
was me) and restarted the incremental. Session 1 (me) remained the same,
session 2,3,4 and 5 started (why 6,7,8,9 never started is a mystery). Session
2&3 started to backup,
4 & 5 decided to formally end.
I know the eyes of Tivoli/IBM are out there...... care to comment? The TSM V3.7
Technical Guide (SG24-5477-00) page 15 claims multi session client support
is available and needless to say is completely transparent to the user. There
is no need
to switch it on or off.
I ponder..... then what value is the resourceutilization and maxnummp parameters
and why isn't this working?
Bill Smoldt wrote:
> Mark,
>
> Oh, that options were as simple to understand as you've stated. Such is not
> the case, and the actual internals of resourceutilization will remain
> obscure even after an explanation, as I learned from my friend Todd last
> week.
>
> >From the description of your system, let me guess that you have at least one
> other mount point besides your 75GB filesystem that you are attempting to
> test, and that those other filesystems are not excluded from your test. If
> so, the behavior you are experiencing is quite normal.
>
> Without the 15 page explanation, let me suggest that a solution to your
> problem may lie in the definition of multiple virtualmountpoints within your
> 75GB filesystem. Otherwise, you will have only one long running consumer
> session session.
>
> Bill Smoldt SSSI
> Storage Solutions Specialists, Inc.
>
> -----Original Message-----
> From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On
> Behalf Of
> Mark Owens
> Sent: Friday, April 14, 2000 10:25 AM
> To: ADSM-L AT VM.MARIST DOT EDU
> Subject: Multithreading w/TSM 3.7.2
>
> AIX Server : TSM 3.7.2
> TSM Client/Aix : 3.7.1
> AIX : 4.3.2 & 4.3.3
> commethod : sharedmemory
>
> Hi All,
>
> With TSM 3.7, Tivoli has provided the resourceutilization parameter in
> dsm.sys
> and the maxnummp parameter when you register your node. To the best of my
> knowledge, maxnummp equates to mount points and when using a tape
> storagepool
> this equates to the number of tape drives that will be used for the backup.
> The
> resourceutilization throttles system resources and the number of sessions
> used for the backup.
>
> While testing with a single node, maxnummp=2 and resour=7 and a 75gig test
> filesystem I'm noticing two sessions are started, two tape mounts occur,
> each
> session performs a backup. Then, after approx 2-3 minutes the last session
> started
> ends....... no error.......tape not full....... after the retention timer of
> 1 minute the
> tape dismounts. The odd thing is the backup has not completed, the remaining
> session
> is left to complete the backup. I'm told TSM 3.7 performs some sort of
> pre-backup
> calculation to determine the optimal number of sessions to start and remain
> active in
> order to complete the backup.
>
> Clearly (depending on the number of resources at my disposal) I'd like to
> complete
> the backup as soon as possible with as many tapes as possible without TSM
> stopping
> the active sessions I have running. Has anyone else experienced this or been
> able
> to have numerous sessions active writing to muliple tapes?
>
> Mark
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