Richard

I am assuming that when you say RMAN, you mean RMAN in conjunction with
the TDP.

The TSM activity log lists the amount of data that RMAN/TDP has
*transmitted from* the Oracle database and through the TDP
(pre-compression). The accounting log shows the amount of data that was
received by the TSM server (post-compression). This should give you your
compression ratio.

Eg Extract from activity log
07-11-2005 19:09:42 ANE4991I (Session: 8351, Node: XXXXXXXX)  TDP Oracle
NT ANU0599 ANU2535I File \adsmorc\orcnt\bph35taj_1_1 = 8060928 bytes
sent

Output from the following select command
select bytes,entity,number from summary where entity='XXXXXXXXXX' and
number=8351

(Number is the session number gained from the activity log)

               BYTES     ENTITY                      NUMBER
--------------------     ------------------                  -----------
             8060939     XXXXXXXXXX           8351


As you can see from my example, the bytes are almost identical, which is
correct as we are not compressing this particular Oracle backup at the
client end.

In your case, you should see that the number of bytes returned by the
select command(Post-Compression) will be less than the number of bytes
shown by the TDP in the activity log and thus get your compression
ratio.


Leigh










-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of
Richard Mochnaczewski
Sent: 07 November 2005 20:27
To: ADSM-L AT VM.MARIST DOT EDU
Subject: [ADSM-L] Oracle RMAN compression ratio

Hi Everybody,

Is it possible to determine the compression ratio of a database backed
up using RMAN to TSM ? I would like to see some stats for the backup
size of the database when having compression enabled or disabled on the
client.

Rich