That is the best summary of modern disk technology I have seen put in
print. Truthfully I am left dizzy trying to understand this stuff.
When I ask questions to understand exactly how everything breaks down
from the logical side to the physical side I am met with blank stares
and then some response about "cache read ahead go back virtual striping
nothing is wrong with our set up must be you we paid too much money for
it to be us" type of answer. Then they send me some big excel
spreadsheet that usually makes almost no sense. Perhaps I am stupid and
I will await a really great Hotsos Conference presentation on the topic
as I am sure I am not the only one that needs it.
"Which is just one example of why virtualization can be seen
as is a con-trick. The vendor "virtualizes" a small number of spindles
into a large number of hypervolumes, then tells you that
your LUN is striped across lots of hypervolumes - but
forgets to mention that your LUN is striped, checkered,
zig-zagged and self-contending on a small set of spindles.
Then when you ask for the management tools to investigate
your performance problem, they either don't exist, or cost
a small fortune - "but you don't need to know because it's
virtualized and striped and there can't be a problem."
--
http://www.freelists.org/webpage/oracle-l
Received on Fri Dec 17 2004 - 09:55:56 CST
