This is going to sound silly, but sometimes it helps to simpify the
problem by taking TSM out of the picture.
-The best thing I use to diagnose network problems is FTP. If you think
the problem is in the network, create a big file, and try to FTP it
between the client and the TSM server disk. If you can't get good
MB/sec throughput with FTP, you are never going to get BETTER throughput
with TSM (because of DB overhead). (And compare it to TSM times with
COMPRESSION OFF, not ON.) And ask your network guy to check the switch
for errors while you are doing it. There are known problems when the
client and switch disagree about the full/half duplex settings, they
only show up as switch errors (and slow throughput).
- If you think the problem is in the server disk, compare a backup
running to disk to a backup of the same large file running direct to
tape. (And watch IOSTAT for high I/O wait times while you are doing
it.)
Simple, but sometimes helpful.
-----Original Message-----
From: Steve Schaub
To: [EMAIL PROTECTED]
Sent: 1/26/01 9:10 AM
Subject: Achievable throughput using Gigabit connections?
I am looking to find out what kind of mb/sec other shops are getting.
Our environment is:
AIX 4.3.3 Server (3466-C00 = H50 2cpu, 1gb mem, 2-gbit ethernet, 1-100mb
ethernet) running TSM 3.7.3.8
3494 library using 3590E drives with 3590K tapes
Switch is Cisco 6509 on a dedicated vlan segment
Client is HP V2200 (16cpu, 12gb mem, 1gbit ethernet dedicated to backup
vlan) running TSM 3.7.2 under HP-UX 11.0
Specifically, when we try to archive a 100gb Oracle database on the HP
(as a file system with approx 450 files, not using EBU/RMAN, residing on
an EMC 3700 Symmetrix), we are seeing aggregate throughput in the
6-7mb/sec range, which translates into approx 4.5hrs. When we watch the
Aix monitor, the gbit interface varies from 15 down to 1.5mb/sec. The
cpu never goes over 20%. The consultant who helped us get this
installed & setup claims that a business down the street with almost
identical hardware/software is able to get a single backup stream to do
80gb/hr. So far we have involved HP, Tivoli, Aix, Cisco, EMC and almost
every techie in our shop without being able to find a conclusive answer
as to where our bottleneck is.
Are other shops seeing anything close to 80gb/hr in a single stream
using gb to gb ethernet connections? Any pointers as to where to look,
or recommended tools for at least diagnosing the problem? Thanks in
advance.
Steve Schaub
Haworth, Inc
email: [EMAIL PROTECTED]
