Veritas-bu

[Veritas-bu] Small files take time on Netbackup

2002-04-19 01:41:42
Subject: [Veritas-bu] Small files take time on Netbackup
From: Simon.WEAVER AT astrium-space DOT com (WEAVER, Simon)
Date: Fri, 19 Apr 2002 06:41:42 +0100
Ahhh I see
My apologies Ang :(
Thanks again Ken! As always, an excellent source of info :)

Thank you all.

Simon Weaver
NT Domain Administrator
Ext. 5544
Tel: 02392-705544 (Direct Dial)
Simon.Weaver AT Astrium-Space DOT com

 -----Original Message-----
From:   Young, Ken [mailto:limelite AT ti DOT com] 
Sent:   18 April 2002 04:48:PM
To:     WEAVER, Simon; ''veritas-bu AT mailman.eng.auburn DOT edu' '
Subject:        RE: [Veritas-bu] Small files take time on Netbackup

I think you misunderstood. Ang is not telling you to set the parameter to
flush the cache after every 10 files because his recommendation is to set it
at 0.

Ang's right. I would definitely check the network settings first and make
sure they are matched with the port. Don't use Auto-Negiotiate. See
http://seer.support.veritas.com/docs/232929.htm.

This may be helpful too: http://seer.support.veritas.com/docs/240887.htm
titled "How to improve backup, restore and duplication performance when
using a Windows 2000 or NT 4.0 media server under VERITAS NetBackup 3.4GA or
3.4.1GA.". For unix server, see:

http://seer.support.veritas.com/docs/183702.htm and
http://seer.support.veritas.com/docs/243197.htm 

Furthermore, according to http://seer.support.veritas.com/docs/233254.htm, 

1) CACHED FILES (handled by Reg value "OTM_Cache_Control"): It is NOT
recommended to change this field from the default value of 0. When this
field is set to 0, the cache file will not grow beyond the size of the
configured "initial cache file" size if the "max cache file" size is set to
any value other than 0.  Since the recommended "max cache file" size setting
is 0, the above limitation is not a factor (see bullet number 3).  It has
been found that leaving this value at its default value of 0 will allow OTM
to operate more efficiently and dynamically on most servers.

And if you are using file compression, see
http://seer.support.veritas.com/docs/239562.htm. It is not recommended that
you change this parameter either.

2) Since your server is NT4 with a 50G file system, your max cache size
cannot be over 2000.

3) A smaller Maximum cache file size will be needed if it has been
determined that there is enough available physical RAM in the server.

Btw, regarding OTM_Error_Control (Controls how OTM reacts when it encounters
an error.), the default is abort. The applicable values are listed below.
Data type is Reg_Dword:

0 = Abort on Error
1 = Disable OTM
2 = Retry OTM

You may have to play with these settings too:

OTM_Quiescent_Timeout: 
Busy File Timeout: Specifies the duration (in seconds) of the quiet period
that must occur so the snap can be taken. The default is 60 seconds. This a
60 second time period in which the quiescent_wait must occur.

OTM_Quiescent_Wait: 
Busy File Wait: Specifies how many seconds to wait for a quiet period to
occur. If this time expires, the backup proceeds but without backing up the
file. The quiet period is a period of time during which no writes are being
performed on the drives or volumes to be backed up. The default is 5
seconds.

I would give Veritas Support a call. They can help make OTM recommendations
for you. Fine tuning OTM is an art sometimes. :-) 


Regards,
Ken Young
Texas Instruments Inc.
(214) 567-5016 

-----Original Message-----
From: WEAVER, Simon [mailto:Simon.WEAVER AT astrium-space DOT com] 
Sent: Thursday, April 18, 2002 6:56 AM
To: 'Ang Chip Chiang NCS'; ''veritas-bu AT mailman.eng.auburn DOT edu' '
Subject: RE: [Veritas-bu] Small files take time on Netbackup


There are over 850,000 files!
I am a little concerned Netbackup would be recreating the cache for every 10
files!

Simon Weaver
NT Domain Administrator
Ext. 5544
Tel: 02392-705544 (Direct Dial)
Simon.Weaver AT Astrium-Space DOT com

 -----Original Message-----
From:   Ang Chip Chiang   NCS [mailto:ccang AT ncs.com DOT sg] 
Sent:   18 April 2002 12:48:PM
To:     WEAVER, Simon; ''veritas-bu AT mailman.eng.auburn DOT edu' '
Subject:        RE: [Veritas-bu] Small files take time on Netbackup

 
Hi,

Try making this ti the NetBackup config. for the OTM:

Initial cache size: 500 
Max. cache size: 2500 
Busy file wait: 1 
Cached files: 0 
Error Control: Abort on error 

If the above Cached files is set to say, 10, then NetBackup will try to
recreate the OTM image after every 10 files. By setting to 0, NetBackup will
take the cache size as reference instead.

Another thing you can do is to force the NIC to communicate in full duplex.
By default it is in auto mode.

Hope that helps.

ACC


-----Original Message-----
From: WEAVER, Simon
To: 'veritas-bu AT mailman.eng.auburn DOT edu'
Sent: 4/18/02 6:35 PM
Subject: [Veritas-bu] Small files take time on Netbackup

Hi again,
Very sorry to bother you, but I wanted some idea on throughput on Netbackup
on NT Server I have an NT Server client with 50GB of Data, and the majority
of the files are all small XML files.

Presently, it has taken 1hr 25mins to backup 17.5GB

How does Netbackup cope with small files, and is there a way to increase
speed?

Many Thanks

Simon Weaver
NT Domain Administrator
Ext. 5544
Tel: 02392-705544 (Direct Dial)
Simon.Weaver AT Astrium-Space DOT com
...
This email is for the intended addressee only.
If you have received it in error then you must not use, retain, disseminate
or otherwise deal with it.  Please notify the sender by return email.
The views of the author may not necessarily constitute the views of Astrium 
Limited.
Nothing in this email shall bind Astrium Limited in any contract or obligation.
Astrium Limited
Gunnels Wood Road
Stevenage
Hertfordshire
SG1 2AS

<Prev in Thread] Current Thread [Next in Thread>