On Thu, 12 Aug 2010, Brad Nicholson wrote:
On 10-08-12 03:22 AM, Arjen van der Meijden wrote:
On 12-8-2010 2:53 gnuoytr@xxxxxxx wrote:
- The value of SSD in the database world is not as A Faster HDD(tm).
Never was, despite the naive' who assert otherwise. The value of SSD
is to enable BCNF datastores. Period. If you're not going to do
that, don't bother. Silicon storage will never reach equivalent
volumetric density, ever. SSD will never be useful in the byte bloat
world of xml and other flat file datastores (resident in databases or
not). Industrial strength SSD will always be more expensive/GB, and
likely by a lot. (Re)factoring to high normalization strips out an
order of magnitude of byte bloat, increases native data integrity by
as much, reduces much of the redundant code, and puts the ACID where
it belongs. All good things, but not effortless.
It is actually quite common to under-utilize (short stroke) hard drives in
the enterprise world. Simply because 'they' need more IOps per amount of
data than a completely utilized disk can offer.
As such the expense/GB can be much higher than simply dividing the capacity
by its price (and if you're looking at fiber channel disks, that price is
quite high already). And than it is relatively easy to find enterprise
SSD's with better pricing for the whole system as soon as the IOps are more
important than the capacity.
And when you compare the ongoing operational costs of rack space, powering
and cooling for big arrays full of spinning disks to flash based solutions
the price comparison evens itself out even more.
check your SSD specs, some of the high performance ones draw quite a bit
of power.
David Lang
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