Hi,
We are backing up to the TSM's 150 GB Diskpool and restoring from the 150 GB
Diskpool as well. Although we haven't tried to back up straight to tape
(the DLT library has 2 DLT IV drives), we still can't explain why restores
from diskpool are faster than the backups using Gigabit. Our backups have
ALWAYS been 10-20% faster. Have other Gigabit users seen this kind of
performance or instance of faster restores? Thanks in advance.
-Vin
-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU]On Behalf Of
Rainer Wolf
Sent: Thursday, October 31, 2002 7:52 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: HELP! Faster Restore than Backups over Gigabit?
Hello Vin,
our tsm-server is just on gigabit and some of the clients are also
there. My guess is that your restore - performance is just
showing what your drive can read ( maybe magstar - drives ? ).
I just assume that you are restorung from tape ... because i got nearly
exact the same throughput when using 1 tape for restore over gigabit.
I also have slower backups, but thats because of a maybe-not-optimal-tuned
disk-pool ( ssa-mirrored) whre our backups are running to.
You just may try backing up direct to tape and see a difference ?
Greetings
Rainer
Steve Schaub wrote:
>
> Paul (or anyone who knows),
> If Vin has the logging mode set to rollforward, does that impact
> performance? I only suggest this because I have had a nagging slowdown
> in some operations and the only change I can really identify is that we
> switched from normal to rollforward logging. Just a wild guess.
>
> -----Original Message-----
> From: seay_pd AT NAPTHEON DOT COM
> Sent: Wednesday, October 30, 2002 10:36 PM
> To: NAPTHEON.COM.seay_pd; VM.MARIST.EDU;.ADSM-L
> Subject: Re: HELP! Faster Restore than Backups over Gigabit?
>
>
> You have lots of RAM, but what is your bufferpool size. For this size
> of machine memory, I would use at least 256MB for the bufferpool size.
> Also beef up the logpool size as well. Your TSM DB and log are very
> small. Do a Q DB F=D command and see what your database hit percentage
> is. If it is less than 98 percent you need to increase the bufferpool.
>
> Did you TSM mirror the Database and Log? If so, it is probably useless
> because you are already running protected disk. Remember, on RAID 1 you
> still have to write all data twice and on read back both drives can be
> used as a source if the RAID card is smart enough to do that.
>
> I am betting that you are overrunning the RAID card during the backup.
> Are the RAID 1 mirror volumes on the same physical SCSI bus as the
> primaries? That could be the issue as well.
>
> Hope this helps.
>
> Paul D. Seay, Jr.
> Technical Specialist
> Naptheon Inc.
> 757-688-8180
>
>
> -----Original Message-----
> From: Vin Yam [mailto:vyam AT QBCT DOT COM]
> Sent: Wednesday, October 30, 2002 11:14 AM
> To: ADSM-L AT VM.MARIST DOT EDU
> Subject: Re: HELP! Faster Restore than Backups over Gigabit?
>
>
> Hi,
>
> Our backups are set for an absolute serialization. We backup and
> restore the same number of files and the same amount of data 42 GB. The
> TSM server is configured in a RAID 1E0 with a ServeRAID 4Mx adapter.
> The client is using a RAID 1. We are going straight to disk since our
> diskpool is 150 GB. We've tried formatting the partition that the
> diskpool is on in 64k blocks, but it hasn't proved much help.
>
> Is there a case where the TSM DB can be TOO large? Our TSM DB volume is
> 1 GB in size and our recovery log is 250 MB in size. We have 4 GB of
> RAM on the TSM server, so we didn't consider this to be a problem.
> Thanks for any help. Please email me if you need more information.
>
> -Vin
> vyam AT qbct DOT com
>
>
> -----Original Message-----
> Forum: ADSM.ORG - ADSM / TSM Mailing List Archive
> Date: Oct 30, 00:08
> From: Seay, Paul <seay_pd AT NAPTHEON DOT COM>
>
> Actually, the 2048 TCPWINDOWSIZE is not supported in NT to my knowledge.
> It is supported in W2K at SP1 or 2, cannot remember, with a registry
> hack. Someone else will have to give the particulars on that.
>
> Be careful comparing restores to backups. Depending on what numbers you
> are using, you may get the wrong conclusions. Make sure it is the same
> files backed up that were restored. Also, look at where your backup is
> going to on your server. If it is going to RAID-5 storage pools, that
> is it. The write penalty on the RAID-5 Array is the cause of the backup
> delay. If you are going directly to tape, I do not know what the issue
> is without a lot more information.
>
> Paul D. Seay, Jr.
> Technical Specialist
> Naptheon Inc.
> 757-688-8180
>
>
> -----Original Message-----
> From: Vin Yam [mailto:vyam AT QBCT DOT COM]
> Sent: Tuesday, October 29, 2002 7:16 PM
> To: ADSM-L AT VM.MARIST DOT EDU
> Subject: HELP! Faster Restore than Backups over Gigabit?
>
>
> Hi,
>
> We just installed Gigabit fiber NICs and an isolated gigabit fiber
> switch. Our restores have increased dramatically from 31.81 GB/hr (8.84
> MB/s) to 56 GB/hr (15.6 MB/s). The backups are still around 35.5 GB/hr
> (9.8 MB/s). The TSM server is very powerful (NT 4.0 SP6a Dual 1.8 Ghz
> P4 w/ 4GB RAM, 150 GB RAID array) and the clients are (Netware 4.2 Quad
> XEON P3 w/ 4 GB RAM). (We've tried changing the TCPWindow Size in our
> dsmserv.opt from 63 to 2048 with no effect) We're running TSM 5.1.1.4
> server and TSM 4.2.3 netware
> client. Any
> ideas? Please email me direct if you have any suggestions or need more
> information. Thanks.
>
> DSM.OPT settings
>
> ** TSM TWEAKS **
> COMPRESSION NO
> LARGECOMMBUFFERS YES
> MEMORYEFFICIENTBACKUP NO
> PROCESSOR 20
> RESOURCEUTILIZATION 10
>
> TXNB 2097152
>
> TCPB 32
> TCPNodelay YES
> TCPWindowsize 64
> ** TSM TWEAKS **
>
> managedservices schedule webclient
> schedmode prompted
>
> -Vin
> vyam AT qbct DOT com
--
----------------------------------------------------------------------------
---
Rainer Wolf mail:
rainer.wolf AT rz.uni-ulm DOT de
tel: ++49 731 50-22482 fax: ++49 731 50-22471
Computing Center, University of Ulm, Germany web:
http://www.uni-ulm.de/urz
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