Veritas-bu

[Veritas-bu] NB51MP3 high cpu loads caused by bpdm?

2005-07-06 18:31:17
Subject: [Veritas-bu] NB51MP3 high cpu loads caused by bpdm?
From: Gregory.Geyer AT Avnet DOT com (Geyer, Gregory)
Date: Wed, 6 Jul 2005 15:31:17 -0700
A trick a Veritas instructor gave me last year was this:

grep out "waited for full buffer" and "waited for empty buffer" out of
your bpdm/bptm logs. 

If you see many "waited for full buffer" in your bpdm/bptm log then the
storage unit disk/tape is waiting for the data buffer to fill.  Tune
down the size of the data buffer so it fills quicker.

If you see many "waited for empty buffer" then the server is waiting on
the storage unit.  Increase the number of buffers.

G.

-----Original Message-----
From: cckat AT reality.ucdavis DOT edu [mailto:cckat AT reality.ucdavis DOT 
edu] On
Behalf Of Kathryn Hemness
Sent: Wednesday, July 06, 2005 3:18 PM
To: Geyer, Gregory
Cc: Kathryn Hemness; veritas-bu AT mailman.eng.auburn DOT edu
Subject: RE: [Veritas-bu] NB51MP3 high cpu loads caused by bpdm?

Thanks.  I'll give the DISK BUFFER settings a try.  I was kind of
wondering if a smaller buffer size might be better.


On Wed, 6 Jul 2005, Geyer, Gregory wrote:

> Date: Wed, 6 Jul 2005 15:00:09 -0700
> From: "Geyer, Gregory" <Gregory.Geyer AT Avnet DOT com>
> To: Kathryn Hemness <kfhemness AT ucdavis DOT edu>,
>      veritas-bu AT mailman.eng.auburn DOT edu
> Subject: RE: [Veritas-bu] NB51MP3 high cpu loads caused by bpdm?
>
> Kathy,
>
> I believe SIZE_DATA_BUFFERS and NUMBER_DATA_BUFFERS are for bptm only.
> I've only just discovered "SIZE_DATA_BUFFERS_DISK" and 
> "NUMBER_DATA_BUFFERS_DISK" for use by bpdm.
>
> However I also experienced shared memory issues with these as we're a 
> heavy disk-staging shop.  These might help your speeds, though I don't

> know about offloading your CPU.
>
> Reference Document ID 273532 for the above info.
>
> G.
>
> -----Original Message-----
> From: veritas-bu-admin AT mailman.eng.auburn DOT edu
> [mailto:veritas-bu-admin AT mailman.eng.auburn DOT edu] On Behalf Of Kathryn 
> Hemness
> Sent: Wednesday, July 06, 2005 2:38 PM
> To: veritas-bu AT mailman.eng.auburn DOT edu
> Subject: [Veritas-bu] NB51MP3 high cpu loads caused by bpdm?
>
> Greetings --
>
> I am running NetBackup 5.1 MP3 on a Sun V240 and using Sun StorEdge 
> 3511 storage arrays with 6TB capacity for backups to disk (not using 
> the disk-staging configuration).  The OS is Solaris 9.
> The backups are first written to the storage array and then staged to 
> tape using cron-script managed duplications so that I can use 
> backupid-files containing backupids having the same retentions to 
> minimize tape mounts.  My tape library is a Qualstar 88264 LTO2 
> library with 3 LTO2 drives.
>
> To optimize read and write speeds the storage arrays, I alternate 
> directing all active backups to one storage array while staging 
> diskimages to tape from the other storage array.  I'm able to 
> alternate the active backup storage unit daily.
>
> In order to complete all of the backups during typical non-workday 
> hours, I've set NUMBER_DATA_BUFFERS to 24 and SIZE_DATA_BUFFERS to 
> 262144.
>
> The backups are finishing in their configured windows, but the CPU 
> load is extremely high. The uptime commands shows a load of 25-40 all 
> during my backup windows and top shows the bpdm processes as using 
> 1.0-1.4 percent of the CPU.
>
> I'm curious to see if there are others seeing high loads caused by 
> bpdm whis is used for both disk and disk-staging storage units.
> I'd like to hear about how others are configuring NetBackup for 
> backups to disk, mostly regarding the size of the disk storage units, 
> NUMBER_DATA_BUFFERS, SIZE_DATA_BUFFERS, and number of concurrent jobs.
>
> Thanks for any information you can give me.
>
> --kathy
>
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--kathy