|
|
How
Much Hay Has Your Car Been Eating Lately? - by Zsolt Kerekes, editor
|
| I think I'm safe in
assuming that the last time you bought a car - you didn't compare its speed or
fuel consumption to a horse. Am I right? Of course you didn't. You compared it
to other cars! |
 |
Editor:- I've been publishing
articles about the
SSD market for over a
decade -
so maybe that's why something in my brain snapped yesterday (May 28, 2008) -
when I was reading yet
another
new article from an SSD vendor about the server acceleration which you
could get from their product.
Because the only competition it mentioned
was
hard drives.
Enough
is enough! - I said.
I can't remember whether the article claimed
their product was 300x or 500x faster in
random IOPS
than a 15K
SAS hard drive -
but as the IOPS in a hard drive haven't changed much since the appearance of the
first 15K RPM products in
EMC's CLARiiON
systems in 2002, and as there may
never
be a 20K RPM drive... The long and the short of it is that every month the
fastest SSDs get
better - while the fastest hard drives remain exactly as fast as they were. So
the HDD versus SSD random IOPS gap gets wider. We haven't learned anything
new!
I'm not denying that these comparisons have been useful in the
past. And they are still useful when a single
2.5" SSD for
example is being compared with a single 2.5" hard drive. But as I wrote in
an article in
2003 when you're looking at what a fast
rackmount SSD can
do for you - you should be calculating how many servers you can save /
or would need to add to get to the same 3x application speedup - not how
many disks.
It's understandable that people refer new products to an
assumed common frame of reference.
I'm sure that a century ago when
the first car owners were talking to their neighbors - they must have made
comparisons like - how much faster they were than a horse.
"It's
amazing. Unlike my old horse my new car doesn't get tired. And I don't need
pasture or hay to make it go - just a few bottles of gas."
And
you didn't get the same stinking mess in the city streets either. (At the time
the Sherlock Holmes stories were being published in the Strand Magazine in 1892
- there was a "green" market carting horse dung out of London to stop
the streets becoming impassable.)
I think I'm safe in assuming that the
last time you bought a car - you didn't compare its speed or fuel consumption
to a horse. Am I right?
Of course you didn't. You compared it to
other cars!
It's a sign of a maturing market when there are enough
products around to compare them to each other, instead of comparing them to
what came before. And we have reached that time with SSDs. It's taken
30 years
- but that's another story.
This new wave of comparing SSDs to each
other kicked off with the article
RAM SSDs versus
Flash SSDs - which is Best? - which included views from leading SSD
oems on both sides of the fence. And other articles have demolished the
myths about SLC
flash SSDs while highlighting the
risks of using
MLC flash in inappropriate server applications.
In my view
comparing SSDs to HDDs does not give you a useful picture when you're looking
at options in the server acceleration market. |
 |
Although I expect that such
weak comparisons will be sprinkled in lite weight SSD articles for the next
few years - it's time for some stronger seasoning. It's time for more articles
by SSD vendors to say how their products and technologies compare with other
SSDs. | |
|
| ...Later:- some
companies are still doing it...
..In contrast - here's
a fact filled vendor-neutral white paper (published November 2008) - which
provides useful measurements and comparisons...
| |
 |
| the Problem with
Write IOPS - in flash SSDs |
Repeating write
operations in some apps
and some flash SSDs can take orders of
magnitude longer than predicted
by IOPS
benchmarks and latency specs.
Time goes by - in
the "play it again Sam"
scene intrinsic to databases -
discrediting
long established performance modeling metrics. | |
|
|
| We have
hundreds
of SSD articles on StorageSearch.com |
Here, below, are some
examples.
- SSD
Market History - lists product and technology milestones in the 30 years of
the SSD market upto the end of 2009.
- RAM Cache
Ratios in flash SSDs - it's important to know the underlying RAM cache
architecture - even if you're happy with the R/W and IOPS performance.
- 2010 - 1st Fizz
in the SSD Bubble? - even the dogs in the street know this is going to be a
multibillion dollar market. Greed will play as big a part as technology in
shaping the
SSD year ahead.
- the pros and cons of
using SSD ASAPs - auto tuning SSD appliances are a new category of SSD
which entered the market in the 2nd half of 2009 to accelerate servers without
needing human tune-ups. How can you tell if they are right for you? And how
well do they work?
| | | |
