In message <[EMAIL PROTECTED]>, "Max Clark" writ

>Given the above:
>1) What would my expected IO be using vinum to stripe the storage enclosures
>detailed above?

That depends a lot on the applications I/O pattern, an I doubt a
precise prediction is possible.

In particular the FibreChannel is hard to predict the throughput off
because the various implementations seems to have each their own
peculiar quirks performance wise.

On a SEAGATE ST318452 disks, I see sequential transfer rates
at the outside rim of the disk of 58MB/sec.  If I stripe two of
them them with CCD I get 107MB/sec.

CCD has a better performance than Vinum where they compare.

RAID-5 and striping a large number of disks does not scale linearly
performance wise, in particular you _may_ see your average access
time drop somewhat, but there is by far no guarantee that it will
be better than the individual drive.

>2) What is the maximum size of a filesystem that I can present to the host
>OS using vinum/ccd? Am I limited anywhere that I am not aware of?

Good question, I'm not sure we currently know the exact barrier.

>3) Could I put all 20TB on one system, or will I need two to sustain the IO

Spreading it will give you more I/O bandwidth.

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