[Beowulf] Re: OT: LTO Ultrium (3) throughput?

Brett Worth brett at worth.id.au
Wed Jun 18 18:31:02 PDT 2008

"David Mathog" wrote:
 >  dd if=/dev/zero of=/dev/nst0 bs=8192 count=10000
 >only moves 21.3MB/sec.


Are you using LTO-3 tapes?  An older gen tape could do it.

Also I have seen instances where /dev/zero is no longer a device but has turned into
a file.  Maybe a big file due to an incorrect "dd of=" option at some stage.  From then on 
your dd tests would be measuring your root disk performance.

Brett Worth

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