In regard to: [Networker] Time differences in writing 1Gb, Maarten Boot...:
On some tapes (not all) I see some interesting time differences on an
otherwise idle machine
Hardware used:
Sun E450 with 2 400 Mhz CPU, 1 GB mem
scsi card: LSILogic LSI22320-R
Exabyte 110L with IBM ULTRIUM2 drives (firmware: 38D0)
data written is a 128k block of gzipped random data from /dev/random
Couldn't this be more a factor of what's coming out of /dev/random than
the tape drive(s) themselves? If your machine is idle, what you're
getting out of /dev/random could vary widely during several runs.
I recommend you take real local data and repeat the tests several times.
This will still be influenced by caching, but at least if you repeat the
tests on real data, you know you're always getting the same source data.
Tim
--
Tim Mooney mooney AT dogbert.cc.ndsu.NoDak DOT edu
Information Technology Services (701) 231-1076 (Voice)
Room 242-J6, IACC Building (701) 231-8541 (Fax)
North Dakota State University, Fargo, ND 58105-5164
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