Veritas-bu

[Veritas-bu] Memory usage under rhel 2.1

2006-10-30 11:15:35
Subject: [Veritas-bu] Memory usage under rhel 2.1
From: jroyer at digitalmotorworks.com (Joe Royer)
Date: Mon, 30 Oct 2006 10:15:35 -0600 (CST)
Memory management in 2.1 is not great (2.4.9 kernel).  I'm assuming you 
are using a hugemem kernel, or it wouldn't access more than 4GB to begin 
with.

Check out
/usr/src/linux-2.4.9-e.59/Documentation/sysctl/vm.txt

You also might want to google:
  "linux 2.4.9 kernel tuning fileserver sysctl"

There are lots of similarities between NBU and NFS on linux WRT memory 
management.

Best answer:  Upgrade to 4.3, it made a world of difference for me.



Date: Fri, 27 Oct 2006 14:02:26 -0300
From: "Edson Noboru Yamada" <enyamada at gmail.com>
Subject: [Veritas-bu] Memory usage under rhel 2.1
To: veritas-bu at mailman.eng.auburn.edu

Hi,
I have a media server (NBU 5.1 MP4) running under RHEL 2.1 AS. 
The server is a SUN V40Z with 8GB RAM. There are 6 LTO2 tape drives 
attached    to it. 
Under normal circunstances, each job is recorded on two tapes 
simultaneously
(on and off-site copy). 
My question is regarding the memory usage, which looks too low. 
NUMBER_DATA_BUFFERS=64, SIZE_DATA_BUFFERS=524288, and the MPX of each 
of the 6 drives is 32.
So, according to the manual, the total shared memory allocate should be: 
NUMBER_DATA_BUFFERS x SIZE_DATA_BUFFERS x MPX x Number of drives = 6 GB.

However, using linux top command, we see a plenty of free memory (5 or 
6GB),    no matter how many jobs are running.

btpm complains also that it?s waiting for empty buffers.

Am I doing something wrong?

TIA 
-------------- next part --------------


-- 
Joe Royer / SysAdmin / Digital Motorworks / 512-692-1028


This message and any attachments are intended only for the use of the addressee 
and may contain information that is privileged and confidential. If the reader 
of the message is not the intended recipient or an authorized representative of 
the intended recipient, you are hereby notified that any dissemination of this 
communication is strictly prohibited. If you have received this communication 
in error, please notify us immediately by e-mail and delete the message and any 
attachments from your system.

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