Been a while, though I've been busy, I have neglected to continue
conversations via this list.

I am so sorry, geeks of the world!

So, what have I been doing?

Oh VMware, as you may already have guessed, digging into mail
subsystems to determine new paths for anti-spam fun things, perhaps
some iDevice programming (and the new Mac App Store - maybe I can make
$20!), more automation projects.

Oh, and storage subsystems!  Almost forgot about those!  Duh!

Nexenta stuff is pretty cool if you wanna check it out, just build up
a system with decent hardware, keep it under 12TB of managed disk, and
you can run it for free.

Caveat: boot disk is 2 mirrored disks, so if you have a 12 bay system,
2 drives to the boot system (and you can't use the rest of the space
for storage, is not counted towards the 12GB, and neither are spares),
leaving 10 disks.

I need to do my own testing, but supposedly building a mirrored pair
disk set can create some HUGELY HIGH disk I/O, for example:

     10 disks...split into....
     	2 disks mirrored
     	2 disks mirrored
     	2 disks mirrored
     	2 disks mirrored
	2 disks spared

and you could rock and roll reaching I/O updwards of 3-10K/sec (I have
*not* tested this myself yet, from the intertubes) depending on your
spindles you chose.

Another option...

     10 disks...split into....
     	2 disks mirrored SSD (write, can be quite small)
     	2 disks mirrored SSD (read, make ~ 1/10th total storage)
     	5 disks raidz2 (dual parity)
	1 disk spared

But as you can see, you don't have many spindles anymore, the above
would top out at about 6TB using 2TB disks, the disks are not very
fast and the SSDs will mask much of it but in the end the I/O won't be
fantastic on a streamed fashion because at some point the data must
move from the write SSD to the spindles.  In the case of the read
performance, hot blocks will be cached onto the read SSDs and you'll
get some very high I/O (and throughput) but your non-hot blocks will
still only be served by the small number of spindles available.  The
mirrored set prior would probably perform better if only because of
the limited spindles.

!!! so there !!!

-- 
Mike Horwath      ipHouse - Welcome home!       [log in to unmask]
        The universe is an island, surrounded by whatever it is
        that surrounds universes. - Berkeley Fortune