| Virident Systems builds enterprise-class
solutions based on Flash and other storage-class memories (SCM).
|These disruptive technologies can
revolutionize the data center and cloud computing but are currently hampered by
significant performance, reliability, and serviceability problems which further
compound in large-scale deployment of SSDs. Virident Systems products solve
Virident Systems was founded by
Valley veterans from Google, Sun Microsystems, Cisco, SGI, and Intel.
Systems - mentions on StorageSearch.com
Editor's comments:- October 2013 - Virident Systems is
now part of HGST. In
this column you can see articles related to Virident, and the past history
of this company as well as my market analysis and also summaries of
interviews I've had with key people in Virident and its partners and
- PCIe SSDs - news
and market guide to the segment in which Virident was operating.
history - shows how the SSD market had progressed from the early days of
obscurity, the progression from a mostly RAM to flash based market, mainstream
adoption in storage and then onto tiered memory systems and the convergence of
memory with processors.
|Prior to its acquisition by HGST - Virident was
a significant advertiser here on StorageSearch.com in the period from February
2011 until June 2013. Above you can see one of its archived ads from that
Virident is 1 of more than 50 companies in the
PCIe SSD accelerator
market, and manufactures fast
enterprise PCIe SSDs.
shipped its first PCIe SSDs in
Top SSD Companies List
in the 2nd quarter of
2011 and in the most recent quarter
Q2 2013 - Virident
was placed comfortably within the elite top 10 group of SSD companies at
Virident designs its own
SSD controllers -
which can be classified as
The company's products have had good
with respect to application symmetry and scalability.
Virident's toughest potential competitors?|
Let's backtrack a bit to contemplate where
all these roads might lead to.
PCIe SSDs are 1 of the
7 main classifications of
SSDs needed to satisfy all enterprise SSD use cases.
But - despite
superficial appearances that "enterprise PCIe SSDs" is itself a
single market segment - there are instead many
within the enterprise PCIe SSD market itself.
stemmed from raw technical and IP
differences in the
design approach of these SSDs. But the PCIe SSD market has been around for long
enough now (5+ years) for important new features and nuances to have emerged
from the business ecosystems and customer experiences surrounding those
original raw products.
I've listed below the vendors who - in my view
- present the most serious competitors to Virident in the enterprise PCIe SSD
market and the key similarities and differences too:-
- Fusion-io - Like
Virident - Fusion-io's SSDs are scalable to large user installations where many
PCIe SSDs are used in one server, also strong software platform. But unlike
Virident - Fusion-io doesn't have an onboard offload processor.
- IBM in the shape of
the legacy PCIe SSD product line acquired from
Texas Memory Systems -
but which is not yet being marketed. Like Virident - the TMS SSD is scalable,
and offloads the host CPU. Unlike Virident - the TMS SSD doesn't have a strong
software platform. That's one of the things which IBM is working on.
- Micron - Like
Virident - Micron's SSD is scalable, and offloads from the host. Unlike
Virident - and as a relative newcomer to the enterprise SSD market - Micron
doesn't have a strong software platform. But that hasn't stopped Micron's SSDs
being adopted by oems who have their own SSD software - for example
- OCZ - Like Virident -
OCZ has a strong software platform. Unlike Virident - OCZ's most successful
enterprise PCIe SSDs didn't use its own controllers - but those from
SandForce - which is
now owned by SSD competitor
LSI. Although OCZ has
other potential suppliers of controllers for PCIe SSDs (including itself) - the
lack of clarity about its future controller IP roadmap for PCIe SSDs is a
I haven't included in the above
list - LSI - and you
may think that deserves an explanation - given LSI's success in grabbing market
share in the PCIe SSD market recently. The reason is that (at the time of
writing this) LSI's own PCIe SSDs and software have been optimized for what I
call entry level deployments in this market - which are optimized for users who
mostly only need 1 fast-enough PCIe SSD in their server - rather than apps
where every slot has a fast SSD.
- BiTMICRO (and
future 3rd party PCIe SSDs based on its Talino SSD controller). - Like
Virident - BiTMICRO has a large architecture controller which offloads from the
host. Unlike Virident - BiTMICRO doesn't have anything much to offer in the way
of software. But it's possible that future "Talino inside" vendors
could pose realistic challenges to slots which are ideal markets for Virident
I also haven't included
Violin Memory in the
above list. Why not? Based purely on the raw specifications of its PCIe SSD
products Violin's product should be up there with Virident. But this product
line is very new for Violin - and while Violin is a proven leader in the
rackmount SSD market
- it's unclear yet whether the company has what it really takes in the way of
marketing resources and knowhow to build a successful PCIe SSD business.
survivor's guide to enterprise SSDs
Earlier Who's who in SSD? profile for Virident - December , 2011
shipped its first PCIe SSDs in
And you might think that maybe the company could mention "PCIe SSDs"
when it comes to rewriting its company profile - instead of that "SCM"
vagary - which is their text at the top of this page.
It's not uncommon
for tech companies to retain an early version of their company description -
written by their founders - as some form of holy writ - for years after it has
ceased to have any valid meaning or connection to what they do.
spoke recently to Shridar Subramanian - Virident's VP product marketing
- the first thing I put to him was - that in some ways in the past year - the
company had given me the impression of still being mentally rooted partly
back in stealth mode.
I had found it difficult to extract details
about the internals of their SSD architecture so I could share them with my
readers (although I had made some educated guesses).
going to change now" he said - because the company had invested a lot more
resources into marketing communications and into writing assets for its web
site as part of the work leading up to the launch of its new
FlashMAX PCIe SSD
To lend weight to my argument about the value of communicating
more openly about SSD architecture - I made the point that the mouse site's
readers are serious minded people and probably included most of the people
they would be trying to reach out to as potential customers.
and said - "I've been reading StorageSearch. myself to learn about the SSD
market for many years - even from the time before I joined Virident. So tell
me what you want to know. And I'll get you the information."
he was as good as his word - following through with a technical briefing and
tons of follow up material some of which I'm still digesting and which will
appear in other places on this site.
But before going into any of that
- a completely unexpected twist for me was some background which helps to
explain the vague wording in the company's own version of its profile - and
which also helps to explain why some parts of their design are the way they are
He said the first product which Virident designed was a
non volatile module for servers which fitted into regular RAM DIMMs but used
NOR flash managed by their own design of controller.
I said I was
aware that NOR flash had mostly been used in mobile phones but hadn't been
adopted in computer SSDs - which all used NAND.
He said the advantages
compared to NAND at that time were simpler random access and much
faster read latency (about 5x).
The disadvantage of NOR was
Despite that, however, Virident had designed a
memory management system which overcame most of the write limitations of the
NOR - and had very good application performance.
But when the
Credit Crunch hit the world economy in 2008 - one of the casualties was the NOR
chip line from Spansion
which Virident had designed into their product. So the company went back to the
drawing board to start again. This time to design a PCIe SSD - and using the
popular SSD market choice of NAND flash.
"But because we had
already solved the problems of slow write performance in the NOR technology our
architecture was giving even better comparative results with NAND."
said Virident's goal at the outset was to design a low server footprint
enterprise flash SSD which would give sustained and predictable performance over
the full spectrum of variable loads that occur in storage apps - and wouldn't
drop off a performance cliff when dealing with small vs large blocks, queue
depths, capacity utilization etc.
Here are some of the features:-
- small form factor - 1/2 length, 1/2 height
RAM flash cache (tiny amount of on-board RAM) and only 1GB approx of server
RAM used to support 1TB of flash
architecture - the card's controller can keep 256 flash memory chips active
at the same time - doing R/W garbage collection etc.
architecture - the product has been designed to operate comfortably with
software that's already out there and doesn't need to be tweaked or rewritten to
work optimally with their product.
perspective editing StorageSearch.com - one of the fundamental differences I
see in PCIe SSD companies - even when they market similar sounding products
- is explained by the background and leanings of the founders and
- non blocking R/W - due to wide (many parallel data lanes) flash-aware
RAID architecture - to help maintain steady performance.
Are they coming at it from a background in semiconductor
technology, CPU design, software or storage architecture?
like Virident views itself as being a dependable enterprise storage company.
Its products haven't been adjusted to shine in any particular hand
picked industry benchmarks. They are intended to work steadily and reliably
without fuss or surprises coping year after year with any of the demands which
users' changing needs may throw at them.
We''ll be reading a lot more
about how that positioning stacks up in the months to come. In the
meantime... if you want to read more - you might want to take a look at
past mentions of Virident - here on StorageSearch.com and the company's
own white papers etc on
I currently talk to more than 300 makers of SSDs and
another 100 or so companies which are closely enmeshed around the SSD
ecosphere - which are all profiled here on the mouse site.
about new SSD companies every day, including many in stealth mode. If you're
interested in the growing
big picture of
the SSD market canvass - StorageSearch will help you along the way. Many
SSD company CEOs read our site too - and say they value our thought leading SSD
content - even when we say something that's not always comfortable to hear. I
hope you'll find it it useful too.
earler editor's comments:- November 2011
Virident's positioning is that it aims to provide consistent enterprise
performance (relative to the variables of block size, how full the SSD is etc)
rather than a product which has speed spikes which vary across dimensions and
time. (Attacking the weaknesses in older models from
isn't unique in having spike free flash SSD performance -
Violin's SSDs have
always had it, Texas
Memory Systems's RamSan-70
delivers it too.
Achieving balanced spike-free acceleration in
flash SSDs is done at the
design stage from an optimal mix of
big vs small
vs fat cache,
optimizing the RAID for flash
(for performance and reliability), using fast
integration with SSD
But performance smoothness and
enterprise features come
at a price. Virident's new MLC PCIe SSDs cost 4x as much per
terabyte as "workstation" grade PCIe SSDs from
OCZ - for example (based on
prices in November 2011.)
If you're looking at products from Virident
you may also think about products from these other companies:-
Texas Memory Systems,
In June 2010 -
announced the immediate
availability of its tachIOn
- a fast PCIe SSD
using SLC flash
- with 800MB/s sustained R/W throughput, 200K sustained random
peak) and capacity options of 200 / 300 / 400GB.
Aimed at the
enterprise acceleration market - the tachIOn's
features include end to end error correction.
quoted as 24 years at 5TB writes / day.
- StorageSearch.com disclosed that search volume for PCIe form factor SSDs had
surpassed that for 2.5"
SSDs for the 1st time something I called - "A tsunami warning event
for SSD vendors addressing the enterprise server acceleration market."
announced the signing
of a reseller agreement with
Virident's tachIOn drive.
announced that it has closed
a new round of funding led by Sequoia Capital.
In December 2010 -
An article on
discussed the write performance of a Virident tachIOn card which was measured
at various percentages full. The author - Vadim Tkachenko - says "Virident's
card maintains very good throughput level in close to full capacity mode, and
that means you do not need to worry ( or worry less) about space reservation or
formatting card with less space."
In April 2011 -
working with SGI they
demonstrated 1 million IOPS performance in a 1U server rack using just 2 of
PCIe SSDs at a system
list price of less than $.05 per IOPS.
In June 2011 -
announced that it has been chosen as a winner of the
Red Herring Top
"I am pleased to see the industry recognize the advances
in our storage technology and understand the market opportunity that Virident
has," said Vijay
Karamcheti, co-founder and CTO, who gave the winning presentation at the Red
Herring Top 100 ceremony. "We have an excellent team here, we are backed by
top investors, and we continue to get positive feedback from both customers and
OEMs. It is going to be a great year for us."
was one of several compatible companies named in
FlashSoft's launch of
its auto tiering SSD
In August 2011 -
Virident's Director of Systems Engineering - Shirish Jamthe presented a
paper at the
Flash Memory Summit called -
Close Look at PCIe SSDs (pdf) which gives you some idea of their thinking.
- Virident Systems
it has completed a $21 million Series C funding bringing its total equity
funding to $50 million. The company also launched its first
PCIe SSD - the
FlashMAX MLC - with 1.4TB
RAID protected (7+1)
capacity and 1.4 Million IOPS with 20 microseconds latency. (1TB MSRP
In August 2012 -
it will ship a new generation of fast PCIe SSDs in September.
II (pdf) has upto 2.2TB usable RAID protected MLC capacity, 103K random
R/W IOPS (4kB 70:30 mix), and 1.1 million random read IOPS (512B), and <80µS
random read latency (4kB) in a ½ length, low profile form factor.
made a strategic equity investment in Virident as part of a
new collaboration agreement which includes remarketing Virident's
PCIe SSDs and working
together to design new SSDs
for the enterprise market.
that its FlashMAX II family had achieved
In October 2013 -
HGST completed the
Virident which ha been announced in
for approximately $685 million in cash.
is the fastest PCIe SSD we've tested when caching with our software... faster
CEO of VeloBit
talking to the editor of StorageSearch.com in May 2012.|
speeds up telco billing queries|
|Editor:- June 19, 2012 - That
legacy versus new
dynasty thing as a way of viewing different SSD companies - is illustrated
in a quote from a customer of Virident Systems -
mentioned in a
"We needed to eliminate the disk-drive
without changing the architecture of the billing system or the customer-care
interface," said David Fruin, VP of engineering at
Vail Systems - a conferencing
technology services provider - which processes more than 48 million billing
records a day on Microsoft SQL Server.
Vail Systems improved
their response times by an order of magnitude and more than doubled their
ability to handle more customers by using Virident's
FlashMAX PCIe SSDs to
accelerate their systems "without requiring any other changes".
Editor's comments:- "SSDs
accelerate telco system" stories are as old as the hills.
what's interesting about this example from Virident is it shows that
PCIe SSDs can do
useful work in high
availability environments which are usually regarded as the exclusive domain
of SAN based SSDs.
|the 3 fastest PCIe
|Are you trying to shortlist flash SSD accelerators according to
comparative benchmark tests?|
the 3 fastest PCIe
SSDs list (or is it really lists?) may help to take some of the
pressure off you. Hmm... you may be thinking that StorageSearch's editor never
gives easy answers to SSD questions if more complicated ones are available.
||But in this case you'd be
wrong. (I didn't say you'd like the answers, though.) ...read the article|
|Virident and NEC publish
new Oracle IOPS benchmark|
|Editor:- February 14, 2012 - Virident Systems
recently published some
results related to the Oracle application accelerator market. |
system was a single
Xeon family based (8x 10-core CPU)
Express5800/A1080a "GX" server - which had 8x 1.4TB
FlashMAX PCIe SSDs
installed - (11TB total) . The integrated solution delivered 1.2 million
and a bandwidth of 9.4 GB/s in real-world Oracle 8k block-size workloads.
VP at ESG Lab - the
company which did the testing for NEC and Virident said - Our evaluations of
(the products in this system) have revealed that they can eliminate the
performance issues common to real-world workloads and deliver extremely high
levels of sustained and predictable performance for mixed-application workloads.
has addressed the challenges associated with many first-generation PCIe
flash devices with the multi-dimensional performance capabilities of its
FlashMAX SCM. Most notably, the Virident solution delivers extremely high levels
of performance for reads, writes, and a mix of reads and writes.
Editor's comments:- the
PCIe SSD market has
become the incubator and market proving ground for nearly all the major new
advances in high performance SSD architecture and associated memory management.
And from time to time all the leading vendors publish new benchmarks to
demonstrate just what you can achieve with their products. Although I've
about placing too much reliance on any single set of benchmark results - it's
interesting to see who is doing how many IOPS with whom and in what context.
|flash wars in
|When flash SSDs started to be used as
enterprise server accelerators in 2004 - competing
RAM SSD makers said
flash wasn't reliable
RAM SSDs had been used for server speedups
- and in 2004 they owned the enterprise market. (Before 2004 - flash SSDs
weren't fast enough and had mostly been used as rugged storage in the
markets - and in space
constrained civilian products such as smartphones.)
By 2007 it was
clear that the endurance
of SLC flash was more than good enough to survive in high
caches. And in the ensuing years the debate about enterprise flash SSDs shifted
to MLC - because when systems integrators put early cheap consumer grade SSDs
into arrays - guess what happened? They burned out within a few months - exactly
Since 2009 new
technologies and the combined market experience of enterprise MLC pioneers
like Fusion-io and
demonstrated that with the right management - MLC can survive in most (but
still not all) fast SSDs.
Now as we head into 1X nanometer flash
generations new technical challenges are arising and MLC SSD makers disagree
about which is the best way to implement enterprise MLC SSDs.
type of so called "enterprise MLC" is best? Can you believe the
contradictory marketing claims? Can you even understand the arguments? (Probably
And that's why marketing is going to play a bigger part in the
next round of enterprise SSD wars as SSD companies wave their wands and reveal
more about the magic inside their SSD engines to audiences who don't really
understand half of what they're being told.
|Editor:- September 9, 2013 - it was announced
today that Virident
Systems will be acquired by WD's enterprise SSD
subsidiary - HGST
for approximately $685 million in cash. |
Virident is a Top 10 SSD
company with its own
SSD controller technology, and a market proven
scalable enterprise PCIe
SSD compatible product line.
The signs that Virident was behaving
like a company which might be imminently acquired (by someone) started to
become clear 2 months ago. However, if anyone had put bets on who that likely
acquirer would be - the most probable name which would have come up in such
conversations would have been
on the heels of an enterprise
SSD marketwide acquisition binge in recent months - this latest move
suggests that HGST will be appearing in rather more enterprise SSD shortlists
It also confirms - if you had any doubts about it - that
the main reason for WD wanting to acquire
Stec recently - had
little or nothing to do with Stec's weak PCIe SSD product line.
|LinkedIn uses Virident SSDs|
|Editor:- August 28, 2013 - Virident Systems
that LinkedIn is a customer of its
comments:- In the
early days of
the SSD market it was usual for SSD companies and their customers to be
secretive about their relationships - especially when users were getting
spectacular commercial results from using SSD acceleration.
users would tell me - they didn't want their competitors knowing how they had
achieved what they were doing using SSDs.
And in those days vendors
were mostly secretive about the identity of their customers too - because
they had invested high costs in
educating users about
SSDs and having done that didn't want their known competitors knocking on
Now everyone has heard about SSDs (as near as
makes any difference) - and the SSD education problem for vendors has shifted
to being - that potential customers learned about SSDs from someone else. - So
that means SSD vendors have to adapt their sales message to fitting into the
SSD schema and market frameworks which customers already have in their heads
- rather than assuming they will be regarded as the font of all SSD wisdom.
another thing which changed in the market in recent years - as more SSD
companies aspired to IPOs,
VC investments or
being acquired -
is that vendors love to talk about their customers - and what they're doing -
even if it's just the same old "new SSD was better / faster/ cheaper than
my old vintage RAID"
Several years ago
Texas Memory Systems
used to circumvent some of their customer reticence by hinting - if you use any
of the big internet shopping sites you were probably using their SSDs.
narrative trend was continued to another level later by
Fusion-io who used to
say - if you use the internet at all - then some of your data may be passing
through their ioDrives.
It would be relatively easy to construct a
list of the top internet sites and then attach brand names of the SSDs they had
been known (or suspected) of using in their server infrastructure. But why
bother? A randomly generated list - picked from the
Top SSD Companies Lists
- might be nearly as accurate. It's impossible to do anything worthwhile
efficiently with vast amounts of data in a timely fashion without using SSDs.
|Virident betas remote PCIe
|Editor:- February 21, 2013 - Virident Systems
beta availability of a new software suite - called FlashMAX Connect - which
enables low latency shared server-side storage and
when used with the
company's range of PCIe SSDs. |
"We're entering the era of
'pervasive flash' in the web and enterprise data centers. However, until today,
such a transformation was not possible due to the lack of availability of
critical software features," said Mike Gustafson,
CEO of Virident. "...The FlashMAX Connect suite is a significant initial
step in actualizing the Virident vision - to enable pervasive flash and
performance storage on the server side."
it's long been known within the SSD industry that these features have been in
the pipeline - because they're based on support at the PCIe switch chip level -
as described at this video -
enterprise SSD designs by
|Seagate invests in
Virident's big SSD architecture|
|Editor:- January 28, 2013 - Seagate today
it has made a strategic equity investment in Virident as part
of a new collaboration agreement which includes remarketing Virident's
PCIe SSDs and working
together to design new SSDs
for the enterprise market.|
"Seagate is thrilled to team with
Virident, a technology leader in one of the fastest growing markets in
enterprise and cloud computing," said Gary Gentry,
senior VP and GM, Solid State Drives at Seagate. "Together, we are working
to develop the next-generation hardware and software solutions in the
comments:- it was obvious a year ago that Seagate's earlier marriage of SSD
IP convenience with LSI
wasn't going to last long or remain monogamous - as LSI and Seagate would be
competing for the same oem design slots in the enterprise market and
furthermore LSI's small architecture
isn't efficient for
scale fast SSD installations. (And in the
LSI didn't have the
controller IP - which is what led to Seagate's stake in
- a top 10 SSD company
- has a roadmap
architecture enterprise SSD controller and drive family which has been
developed in a cleanroom environment - where all the critical IP has been
devleoped by the company.
The obvious gap in the Seagate / Virident
product line is a 2.5"
removable PCIe SSD (to compete with
Micron) - and it's a no
brainer to see that Seagate's experience with this form factor - coupled with
Virident's SSD design skills could quickly result in viable products for this
new market - which will replace upto
25% of the
projected market for fast
|SSD benchmarks and
|Editor:- December 14, 2012 -
the results of a survey of 145 enterprise IT professionals regarding their
requirements for flash-storage purchases. ...click
to see graphical summary (pdf)|
Among other things:-50% said
they have difficulty finding benchmarking tools to accurately evaluate
Of these respondents, 41% find it
difficult to recreate close representations of real-world application
environments, 39% indicate existing benchmark tools do not accurately represent
real-world application workloads, and 20% do not believe benchmark tools exist.
comments:- 4 years ago I published an article -
Can you trust flash
SSD specs & benchmarks? - and I've updated it from time to time over the
years - so it's become a diary of market responses to this issue of benchmark
I know from my conversations with Virident that their (not
so) hidden agenda with performance benchmarks is that their product is benchmark
agnostic and maintains good
performance and age
symmetry across a wide range of workloads you can throw at it. That's why
they would like the industry to adopt a set of more revealing benchmarks which
they have developed. But you can understand the resistance to that idea. I
wrote about the problem that different SSDs look best in different benchmarks in
- the 3 fastest
PCIe SSDs list or is it really lists?
I think this problem is going
to stay with us for many more years. That's because - even if every SSD
vendor agreed that a given benchmark was the most valid today - there are many
new technology and architectural features creeping into SSDs which could
introduce new weaknesses and vulnerabilities which don't show up on current
And that's before you even introduce apps and
optimizations. Customers may say - I don't care if this SSD's performance drops
off in an application which I don't have - because it's the best in the app I
use on most.
It always comes back to better
SSD user education
- and the ability to pick out the points which are salient to your situation and
ignore stuff which may be more important to someone else. Even if it's good for
you - not everyone likes broccoli.
ships FlashMAX II |
|Editor:- November 28, 2012 -Virident Systems
the general availability and shipping of its previously unveiled
FlashMAX II - (fast
enterprise PCIe SSDs) which support Linux, Windows, and VMware ESXi and VDI
environments. Pricing starts at $6,000. |
BlueArc CEO, leaves HDS to steer Virident|
|Editor:- September 20, 2012 - Confidence
about the prospects for flash in the enterprise, and a firm conviction that
a key player which will make a difference to the enterprise SSD market - set
the tone of the conversation I had on Monday with the company's new CEO Mike Gustafson
who was a few days into his new job and briefing me on Virident's
yesterday about his new appointment and the company's $26 million in Series D
Funding. ...more in SSD
|FlashMAX is FlashSoft
|Editor:- August 27, 2012 - Virident's
PCIe SSDs are supported
- it was
The companies say this collaboration includes sales, joint
testing and validation programs, and support and services assistance.
new FlashMAX II
|Editor:- August 9, 2012 - Virident Systems
it will ship a new generation of fast PCIe SSDs in September. |
II (pdf) has upto 2.2TB usable RAID protected MLC capacity, 103K random
R/W IOPS (4kB 70:30 mix), and 1.1 million random read IOPS (512B), and <80S
random read latency (4kB) in a length, low profile form factor.
comments:- I spoke to Shiva Shankar
at Virident about the new product and the
PCIe SSD market.
sees this type of SSD as heading towards a distinctly different storage tier -
and that's the direction of their software focus - even though in the present
market the products have been designed so they can drop in and work with
software and VMs with minimum fuss.
From the design and marketing
positioning point of view Virident has always placed great emphasis on
symmetry and scalability
symmetry. Shiva told me their performance scales linearly. That means if
you have 8 PCIe slots and install upto 8 of the new FlashMAX modules - the
available application performance will be Nx what you would predict from the
single module results.
Virident also say that their performance doesn't
degrade significantly over the lifetime of the product. They call this "Infrastructure
Predictability" - and say it's on the order of 1%.
In contrast -
the performance drop off in some competing enterprise flash SSDs can be more
like 20% to 30%. (This is a vulnerability in some flash SSD designs which has
also been mentioned by STEC
- as an argument in favor of their
asked Shiva if Virident uses
ECC techniques in its SSDs - and (as I expected) he said "no"
(because it's a technique which has been deployed mostly to improve the cost of
SSDs (and components) - whereas Virident is in the fast end of the market
Virident specifically says that its new product is 2x
as fast as a well known competitor. I've heard many such claims before.
the 3 fastest flash
|"...what flash SSD
users get most confused about is the fact that most SSDs on the market show
markedly different behavior depending on whether or not the device is filled to
capacity and what background activities are ongoing..."|
|Vijay Karamcheti, CTO, Virident ...from
his white paper:-
High Sustained Performance with Enterprise Class Reliability (pdf)|
1st generation of NAND Flash-based SSDs were typically advertised as delivering
extremely high read and write bandwidths, particularly compared to disk
subsystems. However, what most users experience is lower than advertised
bandwidth on the smaller block sizes that typically motivate use of SSDs.
such block sizes, not only is the peak performance lower, but perhaps more
disconcerting to most users is the fact that performance varies with usage
patterns, - over time, and with mixed read-write requests of the form typically
encountered in I/O intensive applications.
"...Over the last few
years, the user community has grown increasingly aware of these performance
variations and the need for different benchmarking methodologies, both of which
have led to the current skeptical view of the benefits such devices can bring to
real-world application workloads." ...read
more (pdf) (looks at the root causes and explains how Virident designed
an SSD architecture which doesn't have the same problems)