Interesting speed benchmarks

[Peter Jeremy]

On Mon, 2007-Jan-29 16:45:13 -0500, Robert Huff wrote:
>huff@>>dump 0 -D /tmp/DF -Lau -f /dev/null /usr >& /tmp/null_dump

I'd drop the '-u' and '-D' and add a '-C'.  When sizing the cache,
take into account that each dump subprocess (typically around 5)
will allocate that much RAM.

>huff@>>cat /tmp/null_dump
...
>  DUMP: DUMP: 27485576 tape blocks on 1 volume
>  DUMP: finished in 13818 seconds, throughput 1989 KBytes/sec

That is not good.  Presumably the dmesg output looks sane (ie it's
not running narrow SCSI-1) and dd (or similar) report decent
thruput.

Can you provide some more details on the FS?  What are the block
and frag sizes and how many inodes are used?

-- 
Peter Jeremy
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