Scott:

I've never created the keys, but what I have done (on NT) is to create the
files NUMBER_DATA_BUFFERS and SIZE_DATA_BUFFERS in
/veritas/netbackup/db/config, which works just as well.

As far as guidelines goes, I would first create a bptm log and begin
monitoring the performance of your media servers (these buffer files will
only need to be created on the MEDIA SERVERS).

Based on the information you gleen from there, I would make my changes from
default (8x32 - 8 DATA BUFFERS x 32K ea for non multiplex and 8x64 for
multiplex).

My own experience has been that I have seen increased performance when I
decrease the number of buffers and increase the size, but your mileage may
vary depending on your own environment.

What to look for in the bptm logs?

waited for full buffer

this is the number of times bptm had to wait for a full buffer.  This would
indicate less data coming from the network, so adding more buffers will not
help, but perhaps reducing the number of buffers *MIGHT*.

waited for empty buffer

how many times bptm had to wait for the buffer to empty.  This would
indicate more data coming from the network than the drive can handle so more
buffers would apply here.

The delayed xxxxx times in the logs message

is the number of time bptm waited in the loop for an available buffer (30ms
delay ea. time)


Hope this helps.

David



<><><><><><><><><><><><><><><><><><><><>
David A. Chapa
Consulting Manager
DataStaff, Inc.
847 413 1144
http://www.consulting.datastaff.com
---------------------------------------
NBU-LSERV AT datastaff DOT com - Adv. Scripting

-----Original Message-----
From: owner-nbu-lserv AT datastaff DOT com
[mailto:owner-nbu-lserv AT datastaff DOT com]On Behalf Of Caddell, Scott
Sent: Tuesday, February 20, 2001 9:44 AM
To: veritas-bu AT mailman.eng.auburn DOT edu
Cc: Nbu-Lserv@Datastaff. Com
Subject: [NBUADV-L]: Performance Tuning
Sensitivity: Confidential


I need to do some SCSI performance tuning on my W2K Master (3.4).  I am
pretty
sure I need to create some registry keys in HKLM/Software/Veritas/config
called
Number_Data_Buffers and Size_Data_Buffers, but I'm not sure on how I should
set
the values.  Does anyone have information on creating these keys and a
guideline
on tuning?

Thanks,

Scott Caddell
Intersil Corporation
Palm Bay, FL
-------------------------------------------------------
NBU-LSERV AT datastaff DOT com - Advanced NetBackup Scripting
http://www.consulting.datastaff.com/adv_script_site