> >  Regarding performance issues with multiplexing, I would think that the
> >  higher the number of streams multiplexed to a tape, the slower your 
> >  restore times would be due to the extra tape positioning required.

> John you are absolutely correct!  I have no benchmark data but I don't
> think you really need it to argue that a restore of a single
> contiguous stream will be faster than that of its peer that has been
> Multiplexed with 8 other jobs.

Possibly...   :-)

It also depends on the client.  Personally, I think the situation for
multiplexing was better in the past.  Nowadays, clients and networks
have grown *much* faster, while drive speeds have increased by a smaller
amount.

If a client can backup at 5MB/s and a drive can transfer at 10MB/s, then
putting 2 streams on the drive should not slow down backups *or*
restores.   Both would run at 5MB/s.  

In general, I think you'd need to be using very old clients or very slow
networks to push streams on a drive very high.  With GE connections,
many clients can completely fill a single drive's bandwidth.

-- 
Darren Dunham                                           ddunham AT taos DOT com
Unix System Administrator                    Taos - The SysAdmin Company
Got some Dr Pepper?                           San Francisco, CA bay area
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