| Notebook SSD
Unreliability Story is Unreliable....... |
Editor:- in March 2008 - a
CNET article
insinuating high customer reject rates for
Dell's
SSD based
notebooks was speedily dismissed as
not
true.
Stories about
storage reliability
can't always be taken at face value.
Flash SSDs came from the
military and
industrial applications where bad things can happen - but the SSDs have to
survive. So don't assume from one little story that flash SSDs have intrinsic
secret problems. The
unsecret ones
I'll tell you about.
I remember similar things happening with
ST-506 interface 5.25" hard
drives in the mid 1980s. In my own experience I had a batch with over 50%
DOAs. But how many
were dead when they left the disk factory - compared to how many had been
killed by handling in our own factory was a moot point.
In the early
1990s a leading European PC
maker Amstrad sued both Western Digital and Seagate for market damage
allegedly due to unreliable hard
disks. That bounced around for years and I can't remember how it ended.
There were many other similar stories too. Eventually PC makers learned how to
handle HDDs more gently and HDD reliability and ruggedness improved too.
A
few months ago I predicted that many SSD customers could be unhappy with
mis-sold products not delivering the anticipated application speedups. In that
context I was thinking about EMC
SSDs. Enterprises can only afford fractional capacity shifts to solid state. But
if you don't put the critical files in the SSD you don't get a speedup - just
the check. That means the human part of the integration process is critical to
customer satisfaction. 2 different SSD wizards integrating the same
rackmount SSD in
the same customer site might get 2 different application speedups (or none at
all.)
Back to today's story. I don't know the details - but I do know
that the difference in performance between
flash SSDs on the
market today is like the difference in speed between a pushbike and a Porsche.
Just buying something with wheels doesn't mean you'll get the ultimate speed.
You have to see if it's got an engine. And make sure the wheels are screwed on
tight.
The wheel falling off my wife's car because I didn't tighten it
properly - is another story...
What's that rattling noise and
vibration? - we both asked as the bolts started popping out and the whole car
vibrated badly on our dash to catch the ferry for an island vacation. |
 |
We didn't have time to
stop. I thought it was air turbulence due to me ripping a hole in the underbody
protection sheet when the jack (on our gravel drive) had slipped. So I wasn't
too worried. But I should have been. | |
see also:-
Increasing Flash Solid
State Disk Reliability
93 more
Articles, FAQs, Case Studies about SSDs
Z's Laws - Predicting
Future Flash SSD Performance
Why Consumers Can Expect
More Flaky Flash SSDs!
Understanding Data
Failure Modes in Large SSD Arrays | |
| |
|
| Are MLC SSDs Ever
Safe in Enterprise Apps? |
This is a follow up
article to the popular
SSD Myths and
Legends which, a year earlier demolished the myth that flash memory
wear-out (a comfort blanket beloved by many
RAM SSD makers)
precluded the use of flash in heavy duty datacenters.
This new
article looks at the risks posed by MLC Nand Flash SSDs which have recently
hatched from their breeeding ground as chip modules in cellphones and morphed
into
hard disk form
factors. |
 |
It starts down a familiar
lane but an unexpected technology twist (which arrived in my email while
writing this article) takes you to a startling new world of possibilities.
...read the
article | | |
