Keep in mind the reason for multiplexing is to get enough data to the tape
drive to keep it streaming at maximum speed (average 25GB/hr for DLT 8000).
This means that if you have fast network pipes, and decent servers, you
should be able to achieve that thruput using 2-3 streams. In other words, 6
is overkill. You need to strike a balance. Here are some documents that
should help you.
NetBackup for Windows performance tuning:
http://seer.support.veritas.com/docs/248373.htm
NetBackup for Unix performance tuning:
http://seer.support.veritas.com/docs/240733.htm
Steve Dvorak
Are you ready for VERITAS NetBackup? Test you knowledge on our NetBackup
Self-Assessments:
http://www.veritas.com/education/quicktips/Assessment.jhtml
-----Original Message-----
From: Sen [mailto:discussion.groups AT gmx DOT net]
Sent: Friday, April 18, 2003 8:22 AM
To: Steve Dvorak; Christopher Baughman
Cc: netbackup-l; nbu-lserv; veritas-bu AT mailman.eng.auburn DOT edu
Subject: Re: [BackupScripts-L] restoration time
multiplexing (MPX) is set to 6 during backup to reduce the backup time. i am
backing up about 100GB of data files. Is there any other option to speed up
the restoration time other than reducing the MPX no. ??
----- Original Message -----
From: "Steve Dvorak" <sdvorak AT veritas DOT com>
To: "'Sen'" <discussion.groups AT gmx DOT net>; "Christopher Baughman"
<baughmac AT overture DOT com>
Cc: "netbackup-l" <netbackup-l AT yahoogroups DOT com>; "nbu-lserv"
<nbu-lserv AT dsihost-srv01 DOT com>; <veritas-bu AT mailman.eng.auburn DOT edu>
Sent: Friday, April 18, 2003 10:02 PM
Subject: RE: [BackupScripts-L] restoration time
> Are you using multiplexing (MPX)? If so what value is it set to?
> Multiplexing allows you to have multiple clients backup to a single
> tape device, thus driving the device at close to rated speeds, but it
> is interleaving data on the tape. I.e. if you have MPX set to 10, 10
> clients would deliver data to the device and essentially Client1 would
> have a
piece
> of data every 10 "blocks". Therefore when doing a restore it would
> have
to
> read Client1 data, skip 9 "blocks", read more Client1 data, skip 9
"blocks",
> and so forth. This *could* be the reason, if you are using a high MPX
> number - recommendation for DLT 8000 drives is 2 to 3 MPX. Other
> factors that affect restore time are, how quickly the client can
write
> data to disk, speed of the network pipe, or even some erroneous bug
> somewhere. In general you should be able to restore 12-18GB per hour.
> Steve
>
>
> -----Original Message-----
> From: Sen [mailto:discussion.groups AT gmx DOT net]
> Sent: Thursday, April 17, 2003 7:03 PM
> To: Christopher Baughman
> Cc: netbackup-l; nbu-lserv; veritas-bu AT mailman.eng.auburn DOT edu
> Subject: Re: [BackupScripts-L] restoration time
>
>
> i am using a DLT 40/80, it took me 5+hrs to restore only 3.3GB
> of data!
> any idea?
>
>
> ----- Original Message -----
> From: "Christopher Baughman" <baughmac AT Overture DOT com>
> To: "Sen" <discussion.groups AT gmx DOT net>
> Sent: Friday, April 18, 2003 12:08 AM
> Subject: RE: [BackupScripts-L] restoration time
>
>
> It shouldn't take too long, but that can best be answered based almost
> entirely on your configuration. A good starting place, though, is to
> take how long it takes to back up that data, and multiply that by 1.5,
> or even double it. That is a very loose way to look at it that gives
> a fairly
close
> time range. It is rare that I get a restore time that equals the
> backup time.
>
> -----Original Message-----
> From: Sen [mailto:discussion.groups AT gmx DOT net]
> Sent: Thursday, April 17, 2003 8:33 AM
> To: netbackup-l; nbu-lserv; veritas-bu AT mailman.eng.auburn DOT edu
> Subject: [BackupScripts-L] restoration time
>
>
> hi all,
> can i have some feedback on how long it takes for you to restore 3 GB
> of data using netbackup datacenter 3.4 ? thanks
>
>
> _______________________________________________
> NBU-LSERV AT datastaff DOT com - Advanced NetBackup Scripting Maillist
> http://dsihost-srv01.com/mailman/listinfo/nbu-lserv
> Check out the Advanced Scripting Website
> http://www.NetBackupCentral.com
>
>
>
>
> _______________________________________________
> NBU-LSERV AT datastaff DOT com - Advanced NetBackup Scripting Maillist
> http://dsihost-srv01.com/mailman/listinfo/nbu-lserv
> Check out the Advanced Scripting Website
> http://www.NetBackupCentral.com
>
> _______________________________________________
> NBU-LSERV AT datastaff DOT com - Advanced NetBackup Scripting Maillist
> http://dsihost-srv01.com/mailman/listinfo/nbu-lserv
> Check out the Advanced Scripting Website
> http://www.NetBackupCentral.com
>
>
>
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