the fastest SSDs|
Can you trust SSD specs?
how fast can your SSD
- making the same SSD - with less flash
factors which influence
and limit flash SSD performance
Inanimate Power, Speed
and Strength Metaphors in SSD brands
will SSDs end
bottlenecks? - and cure all my server speed woes?
|how to avoid hot pluggable
PCIe SSD failures|
Editor:- December 3, 2013 - What happens if you
test PCIe SSDs for
their sensitivity to data
corruption or even failure
- in the event of
You'd think that with more hot pluggable products coming
into the market -especially in the
2.5" form factor
- that the experimental outcomes would be known by the designers and problems
debugged so that users wouldn't have to worry.
In August 2013 Quarch Technology
launched some special
test equipemnt to inject power related faults into PCIe SSDs - and the
company today announced
it has extended this range to automate power line error testing of PCIe SFF
Technical Director at Quarch Technology told me today that "Almost every
combination of test kit we have tried in Quarch (a number of friendly customers
lent us kit and eval drives to get the new module up and running) has failed in
some way. Sometimes failing to come back up again nicely, sometimes with a full
BSOD which will almost
certainly have risked data loss."
memory channel SSD vs PCIe SSD write latency - 3rd party
Editor:- November 7, 2013 - Although it's possible to
make estimates of how a new type of
will perform compared to what already exists - the interplay of applications
software, systems software and a new
controller design -
means that initial assumptions can easily be out by a factor of x2. And even if
you have accurately guessed what the weak points and the strong points are in
the product's performance
symmetries - it's only when you start to see
that you can have more confidence in your
models of what's
So if you've been wondering how Diablo's
storage compares with PCIe
here to a new whitepaper (pdf) which includes some useful data. The
application isn't important but it's the first public glimpse which goes
usefully beyond the graphs shown in the product launch documents.
highlight for me is - a mean write latency of about 30µS for MCS compared
to about 100µS for PCIe SSD- at a particular R/W ratio which may of
course look nothing like your own setups. ...more in SSD news
Nimbus scores $40 per virtual desktop in IOmark-VDI
October 1, 2013 - I was talking recently to Tom Isakovich,
CEO and founder of Nimbus
Data Systems about the state of the market and a possible date for an
IPO (which you can read more about in
that we moved onto the subject of
customers buy SSD arrays - and we traded stories about some of the
explanations which get tossed around like
IOPS per dollar -
which when you scrutinize them in any detail are ridiculous. We've both seen
leading edge silicon SSD companies put nonsensical graphs into their marketing
presentations which don't lead you anywhere useful in the real world if you
follow the superficial analysis. (That's because these vendors don't make
systems - and are many steps removed from genuine enterprise thinking.)
said most of his customers couldn't tell you how many
apps were demanding.
I said I've been writing about the "cost
of satisfying a given number of virtual users for a particular type of app"
as being a useful comparison figure (for storage). We both agreed that even if
enterprises don't know for sure what their throughputs or IOPS are - they have a
good idea of how many users they're trying to serve within their organization or
at customer facing web interfaces. The payroll tells you one, the marketing
people can tell you the other. And accounting can tell you how much it all
costs. You don't need storage
analyzer tools to get a feeling for where the ground level lies.
our conversation had already veered towards the subject of a simple way that
users can compare the costs of SSD storage for particular types of apps - and
as I'd asked the question - he said there was a benchmark called IOmark-VDI
which Nimbus had participated in recently with the
He said he went into the process because he thought it might be a good thing to
try out - and was gratified to found out that it shows the Nimbus product in a
very good light with a
under $40 per virtual desktop (pdf) achieved by a 2U Nimbus system
supporting up to 4,032 linked clone VDI images.
measuring enterprise SSD performance - intro by Micron
August 23, 2013 - EDN today
published a introductory article on the subject of
enterprise SSD performance - written by Doug Rollins, Senior
Applications Engineer at Micron
- which could be useful for newcomers to this topic as it expounds some of the
basic assumptions and jargon. ...read
Can you trust flash SSD
specs & benchmarks?
FIO's ION software enables Breakthrough Shared Storage
Editor:- June 13, 2013 - The performance of
Accelerator software - which you can add to its PCIe SSD cards, any
standard server and some FC adapters to roll your own SAN
rackmount SSD -
is the point of a new
blog by the company
today which celebrates recent benchmarks for
2, 4 and 8
processor HP server configuartions (pdf).
Stec's profiler removes guesswork in sizing SSD caches for
Editor:- May 21, 2013 - Stec today
that it's offering a free profiling tool -
Profiler - which can enable users to determine how much benefit they would
get from using its
(SSD caching software) - before they even install any SSDs.
company says that the "non-disruptive installation" can save hours of
administrative trial and error by recommending the optimal block size, and the
capacity and type of SSDs to be used for maximum performance gain.
SSD performance characteristics and limitations
March 15, 2013 - published today - the new home page blog on StorageSearch.com is -
a toolkit for
understanding flash SSD performance characteristics and limitations.
brings together in one place many of the tools I use every day when thinking
about and assessing SSDs.
in memory database even better with FIO's flash
November 20, 2012 - McObject
recently released new
benchmark results which indicate that the in-memory database company is not
so unfriendly to flash SSDs as you may have thought from reading earlier
company positioning papers.
It seems that a software product - which
was originally designed for the DRAM-HDD world - is a good fit in the flash SSD
world too - if you have the right scale of data and the right SSD. ...read more
new article - adaptive flash care IP (including DSP)
June 19, 2012 - A few months ago I promised readers that I would publish a
tentative list of SSD companies who use what I loosely called
DSP technologies in SSD IP" in their new designs. .
of the most important design techniques being used in some leading flash SSDs
- in which the SSD designer can adapt the reliability, speed and power
consumption of the SSD - not based on some faw away population model of flash
chips - but optimized for the chips in each SSD - and adapting the
controller behavior to
what is measured and learned from interacting with the flash chips installed.
This is a market changing technique.
Nimbus publishes tick test results
25, 2012 - Nimbus Data
that several key performance and operational characteristics of its
have been validated by Demartek.
Editor's comments:- it's a complicated business doing
meaningful SSD tests
which can be used as an input into performance modelling. And I've seen many
vendor funded SSD test reports which failed in that respect. But recently - as
the market has got more experienced - some SSD vendors are changing the
emphasis of their sponsored reports to show that their products can walk and
chew gum at the same time. That's the message I pick up from this Nimbus press
release. How much gum? And how brisk the walking pace? It will suit some users
more than others.
NVMe Consortium aims at PCIe SSD compatibility testing
March 12, 2012 - UNH-IOL
accepting founding members for the laboratory's new
which will provide a vendor neutral location for members to test conformance of
their PCIe SSD related
products aimed at the NVMe compatible
market. See also:- storage
suite could speed up auto-tiering SSD evaluations |
|Editor:- November 29, 2011 -
availability of its Disk I/O Ranger software analysis tool for Windows
The company says this will help users diagnose and
understand disk storage access performance problems and to to verify that QoS
levels are being met at the application/file/device level. It could also
simplify the evaluation of
appliances by collecting real-time metrics.
I asked Tom West, President of hyperI/O what he was seeing of the SSD
market from his perspective of selling storage analysis tools. He said -"One
of the major users of the hIOmon software is listed within the top 10 of your
latest - Top 20 SSD
ESG publishes test report on WhipTail's iSCSI SSD
August 31, 2011 -Enterprise
Strategy Group has
a test report on WhipTail
Technologies' 2U iSCSI
SSD appliance in a simulated 300 desktop VMware / W7 environment.
ran glitch free - even when a flash drive was removed. ESG didn't have fast
enough servers to stress test the performance - so they only verified 90% of
the rated 250K IOPS.
Microsemi reports shake rattle and roll SSD results
May 19, 2011 - Microsemi
today announced that its TRRUST-STOR
(2.5" rugged SSDs) are the industry's first SSDs to pass zero-failure
testing at vibration
levels that are consistent with the industry's most severe environments.
"No other SSD manufacturers have published zero-failure results
at this level of vibration testing, which was conducted while our drives were
fully operational, reading and writing data," said Jack Bogdanski, director
of marketing for Microsemi. "The ability for SSDs to perform flawlessly
under adverse environmental conditions is becoming increasingly important for
applications where it is critical that data be protected at all times."
Microsemi's SSD units were pre-conditioned at 85°C for 336
How and why to monitor VM Performance
February 23, 2011 - How
to Proactively Monitor VM Performance is a new article on
Data Center POST written
by Alex Rosemblat,
Product Marketing Manager at VKernel
- who says "Proactive monitoring of a virtualized data center can assist
in finding potential performance problems before they occur..."
comments:- OK he says a lot more than that - and that's why I mentioned his
I used to do a lot of performance analysis in my
pre cut and paste
career because I designed systems with guaranteed apps response times. And
in my current job I always check my stats before I look at my email. So I have
a lot of empathy for the storage
test and analysis market. The more you understand about the internals of
complex systems the less likely you are to get mugged by them. ...
read the article
SandForce publishes list of approved test tool partners
January 31, 2011 -SandForce
has started a directory of companies, tools, technologies and services to
help SSD designers integrate its
SSD processors and get
them to market more quickly.
Each member company in the new
Trusted program ensures that their products and/or services fully
support SandForce SSD Processors and provides response to SandForce customer
inquiries within 24 hours while committing to high-priority support for fastest
Editor's comments:- 6 out of the 7 initial
companies in the new program provide
test / design verification
test report for LSI's PCIe SSD
Editor:- January 3,
2011 - Demartek
has published a
report (pdf) which evaluated the performance of a single
PCIe SSD made by
WarpDrive - $11,500) in a simulated high traffic web server environment in
which the activities were mostly reads.
The test compared performance,
rackspace, electrical power and cost of the SSD based system compared to a
conventional HDD based system and showed that for high traffic websites the SSD
solution is significantly better in all respects. ...read
the article (pdf)
Xyratex expands HDD test assets
8, 2010 - Xyratex
that it has acquired
the HDD component test
related business and assets of Magnetic
Recording Solutions, Inc. (MRS), including a 10 person development team.
This coincides with the recent acquisition of the assets, as well
as the development team, of Optical Systems
Corp - a respected provider of
technology to the disk drive industry.
A key element of Xyratex's business strategy is to expand its
portfolio of test and process technology within the hard disk drive industry.
The acquisition of MRS will combine Xyratex's industry-leading expertise in high
volume disk drive test, servo writing, and media cleaning, handling and
inspection technologies with MRS' extensive experience in complex media testing
and head characterization.
Peeking inside the loop of ioMemory
November 12, 2010 - Fusion-io
has said it
ship a web based control panel - called ioSphere - for monitoring,
performance and controlling its SSDs sometime in Q1, 2011.
Editor's comments:- Usually when you retrofit software based analysis
and control functions to storage networks there's an impact on performance. As
spinning hard disk media
is very slow compared to spinning electrons - this doesn't matter - especially
when using fast multi-core CPUs.
But when you're talking about
those precious micro-seconds that a new software agent spends fooling around
with your data-flows can interfere with smooth running. Although SSD
companies have many times in the past announced such functionality for legacy
SAN based SSDs (for
launched the WhatsHot SSD analysis tool) real-time SAN SSD analyzers have
mostly stayed out of the customer's mission critical cabinets and remained
locked in the developer's labs.
Will ioSphere be any different? -
Knowing a bit about the thinking behind Fusion-io's SSD controller architecture
- which I discussed in an
their CEO in the summer - I anticipated that Fusion-io's ioSphere would be
different. Why? - Because the host server processor is inside the
SSD controller loop
and all the critical control state diagrams are already in the software
stack. So I asked for confirmation about this guess.
Fusion-io's VP of
product and technical marketing, Gary Ornstein, told me - "Your assumption
is correct. There is no overhead. The ioSphere software is providing insight to
information that is already collected within our ioMemory modules"
you look at the philosophy of the Fusion-io designs - one view you can take is
that the SSD makes the host CPU work faster - because it speeds up access to
the data. Another view - equally valid - is that because the host CPU is doing
work for the flash memory - the faster the user's CPU - the faster the SSD. And
the converse is true - which is it that the SSD operates slower when it's used
in tandem with a slower host. Yet another way of seeing these roles is that
both the CPU and the SSD are responsible for the speed of running the apps
together - and you can trade CPUs for SSDs - something I used to call
SSD CPU equivalence. It
may be that fusion of function - which led to the company's founders choosing
the name Fusion-io. Next time we talk I'll remember to ask about that.
pushing the SSD testing rock farther up the hill
August 25, 2010 - I'm mostly resistant to the idea of rehashing recent news
stories - but yesterday while talking about new SSD technologies a reader
asked me to take another look at
performance testing guidelines - which I reported on
a month ago.
said I had been surprised it took
SNIA so long to look at
these issues - because I had been aware of "Halo effects" in
flash SSD benchymarks for years - and commented - "But I guess member
led ORGs have a built in lag factor and only move at the speed of the
slowest exec members."
The reader - Neal Ekker -
whom I knew from his time at
Texas Memory Systems -
put up a spirited defense for this particular ORG opus and said...
all known about the fishy-ness of SSD performance claims for years. But I'd like
to draw attention to what an impressive accomplishment the SNIA SSS PTS
represents, no matter its technical merits or ramifications. I watched it
happen, and I can tell you it was an amazing POLITICAL achievement. And
I don't mean that in a negative way. Any time there's more than one person in a
room, there's politics. For a collection of engineers representing both their
own egos and the interests of their employers to finally agree on even this
rather bare-bones beginning standard was just remarkable to observe. I can't
begin to give enough credit to some of the chief movers and shakers.
Neal Ekker added - "This is why I want more attention focused on
the SSS PTS right now, so we don't lose momentum entirely. There's still plenty
of work to be done. We need additional companies and fresh faces and energies to
step up and push this rock a little farther up the hill."
Editor's comments:- During the majority of the SSS PTS development Neal
Ekker served as the SNIA SSSI Education Committee Chair. He's now a for-hire
independent SSD marketing consultant. ...Neal's bio,
PTS (pdf), Storage
||Megabyte liked to keep his systems
in peak condition.|
|"The more you study
the characteristics of different SSDs - the quicker and more easily you will
start to anticipate useful behavioral characteristics of any new SSD - and
assimilate it in your plans. And you'll start to recognize symptoms of "missing
technical information" too."|
|flash SSD performance
characteristics and limitations |
|"If repeat writes to
the same small address range (same flash blocks) is interspersed with read
operations (what I call - the play it again Sam scenario - which occurs in
database tables) the performance outcome varies significantly between different
designs of flash SSDs." |
|the Problem with
Write IOPS in flash SSDs|
management in flash SSDs|
|This is an introduction to the thinking behind
one of the many vital functions inside a flash
media defect quality in new flash memory chips has grown steadily worse in the
past 10 years as geometries have shrunk.
||This article enumerates
the scale of the problem and explains how intrinsically dodgy flash memory
is transformed into dependable flash SSDs which you can entrust with your data.