Richard Elling wrote:
On Jul 30, 2009, at 9:26 AM, Bob Friesenhahn wrote:
Do these SSDs require a lot of cooling?
No. During the "Turbo Charge your Apps" presentations I was doing around
the UK, I often pulled one out of a server to hand around the audience
when I'd finished the demos on it. The first thing I noticed when doing
this is that the disk is stone cold, which is not what you expect when
you pull an operating disk out of a system.
Note that they draw all their power from the 5V rail, and can draw more
current on the 5V rail than some HDDs, which is something to check if
you're putting lots in a disk rack.
Traditional drive slots are designed for hard drives which need to
avoid vibration and have specific cooling requirements. What are the
environmental requirements for the Intel X25-E?
Operating and non-operating shock: 1,000 G/0.5 msec (vs operating shock
for Barracuda ES.2 of 63G/2ms)
Power spec: 2.4 W @ 32 GB, 2.6W @ 64 GB. (less than HDDs @ ~8-15W)
MTBF: 2M hours (vs 1.2M hours for Barracuda ES.2)
Vibration specs are not consistent for comparison.
Compare:
http://download.intel.com/design/flash/nand/extreme/319984.pdf
vs
http://www.seagate.com/docs/pdf/datasheet/disc/ds_barracuda_es_2.pdf
Interesting that they are now specifying write endurance as:
1 PB of random writes for 32GB, 2 PB of random writes for 64GB.
Except for price/GB, it is game over for HDDs. Since price/GB is
based on
Moore's Law, it is just a matter of time.
SSD's are a sufficiently new technology that I suspect there's
significant probably of discovering new techniques which give larger
step improvements than Moore's Law for some years yet. However, HDD's
aren't standing still either when it comes to capacity, although
improvements in other HDD performance characteristics has been very
disappointing this decade (e.g. IOPs haven't improved much at all,
indeed they've only seen a 10-fold improvement over the last 25 years).
--
Andrew
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