>> On Tue, 4 Apr 2006 10:14:50 -0700, Andrew Carlson <naclos AT SWBELL DOT NET> 
>> said:

> The speed of the random access disk pools is phenomenally better than
> the file device class - not sure why though

When you're writing to DISK pools, writes round-robin through the
volumes.  This is usually better for the underlying disk subsystem
than lots of serial writes. (at least it's been so for all my disk
subsystems).

> It takes alot of time to predefine the volumes.  We were finding it
> took about 19 hours to predefine 2TB.  We were able to run 8 of
> those, so it ended up taking 19 hours to predefine 16TB, but that is
> still a long time.

I don't get the predefined volumes bit; don't see how it could be a
win.  My FILE strategy has been 10-20GB files, in profusion.  This
keeps individual operations sane in length.

> My plan is to move data off of random access volumes on the weekends to
> help prevent fragmentation.

If you're using DISK as a temporary holding pool, I'd expect
fragmentation to be irrelevant.  For permanent storage, however, It'd
be huge.


- Allen S. Rout