I won't call this comparing apples to oranges but it might be Granny Smiths to Red Delicious... I suggest to all our clients that they run TSM client software compression and 90% do but some don't (and often it is because of valid reasons such as servers that house only blah.tar.Z already compressed files, etc...) BUT I also run with the most compression I can get our of my TSM server's 3590 tape drives... so a lot of data is being 1st software compressed by the client and then hardware compressed by my 3590 drives... I'll list some numbers below but basically it seems like I only get 91+% of my tape capacity for one environment and 88.7+% of my tape capacity for another environment with double compression. All this is based on how much you trust the numbers because in an environment that I DON'T DOUBLE COMPRESS... check the numbers at the very bottom ;-) What do I see... Estimated Capacity(MB) (full 3590-J tapes in 3590-B1A drives, with no estcap set) --------- 9,191.0 9,193.6 9,112.9 9,952.8 9,356.7 9,200.2 9,220.9 and Estimated Capacity(MB) (full 3590-K tapes in 3590-E1A drives, with no estcap set) --------- 35,995.9 35,407.7 35,377.0 35,549.4 35,547.0 35,658.3 35,328.8 and Estimated Capacity(MB) (full 3590-K tapes in 3590-E1A drives, with no estcap set) NO CLIENT COMPRESSION... --------- 253,780.6 216,788.5 250,530.4 258,249.1 788,268.4 181,304.0 213,428.1 241,045.4 256,423.9 249,354.7
-----Original Message----- From: Jason Stoessler [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 17, 2002 10:21 AM To: [EMAIL PROTECTED] Subject: Software/Hardware compression? Hi All, I know in other products that you can not run software compression and hardware compression concurrently. I have been told that it results in the files reverting to an almost uncompressed state. What I need is to know if the same applies to TSM. My company are thinking of purchasing TSM so if anyone knows of an official statement from IBM/Tivoli that I can be referred to that would be appreciated. The software platform will be Solaris and the autochanger is an STK L700 with 9840 fibre drives TSM 4.2.1.7. Jason Stoessler Guardian iT
