SSD Performance

What’s In My SSD? SLC, MLC, or TLC?

SLC, MLC, or TLC?Someone recently asked The SSD Guy if there is a way to determine whether an SSD is SLC, MLC, eMLC or TLC.

I found it a little odd to be asked this, since most vendors tell what kind of flash they use in an SSD’s specifications, especially if it’s SLC.

Not finding it there then the next thing I would look at is the price.  Raw SLC NAND flash now sells for about 6-10 times as much as its MLC counterpart, so an SSD with a price of around $1/GB is likely to be MLC and one that sells for around $10/GB is probably SLC.

TLC SSDs are really rare.  There is the Continue reading

Comparing Samsung’s Planar and V-NAND SSDs

Samsung 3D V-NAND Press PhotoSamsung recently introduced  its 3D V-NAND-based 850 SSD which, according to The Tech Report, uses the same MEX controller as the company’s 3-bit planar SSD, the 840, introduced last year.

Samsung said in its keynote speech at the 2013 Flash Memory Summit that V-NAND consumes an average of 27% less power and runs at least 20% faster than its planar counterpart in an SSD application, all while providing ten times the endurance.  It’s only natural to assume that this would allow designers to produce a V-NAND SSD that would significantly outperform its planar NAND counterpart.

The SSD Guy had an opportunity to review Continue reading

New Report Posts Results of IT Manager IOPS Survey

From Report: "How Many IOPS Do You Really Need?"Tom Coughlin and I have just released a new report that helps shed a lot of light on a pretty challenging subject: We asked nearly 200 IT managers to tell us how much storage performance their systems require.  They provided candid replies about their IOPS, latency, and capacity needs for a number of leading applications.

The results of this survey are compiled in a 80-page report titled How Many IOPS do you Really Need?  This one-of-a-kind report provides responses for all of Continue reading

White Paper: Matching Flash to the Processor

Moving flash into the memory channel to get fast parallel performance I have just added a new white paper onto the Objective Analysis website: Matching Flash to the Processor – Why Multithreading Needs Parallelized Flash.

This document examines the evolution of today’s CPUs, whose clock frequencies have stopped increasing, but now exploit parallelism to scale performance.  Multiple DRAM channels have also been added to performance computing to add parallelism to the memory channel.

Storage hasn’t kept pace with this move to parallelism and that is limiting today’s systems.

New NAND flash DIMMs recently introduced by Diablo, SanDisk, and IBM, provide a reasonable approach to adding parallel flash to a system on the its fastest bus – the memory channel.  This white paper shows that storage can be scaled to match the processor’s growing performance by adding flash DIMMs to each of the many DRAM buses in a performance server.

The white paper is downloadable for free from the Objective Analysis home page.  Have a look.

Kaminario Seizes SPC1 Title Again

Storage Performance Council LogoFor the second year in a row little Kaminario has beat the large established storage array vendors to produce the highest SPC1 benchmark rating at 1.24 million SPC-1 IOPS.

The results of the Storage Performance Council’s SPC-1 report, show Kaminario surpassing last year’s record performance by 20k IOPS.

Interestingly enough Kaminario set the 2012 record using DRAM while this year the company was able to do it with its fourth-generation all-flash K2.

Why is the SPC1 test so highly respected in Continue reading

Solving SSD Power Spike Issues

The following guest post was contributed by Doug Dumitru the CTO of Easy Computing Company (EasyCo), a software R&D company which develops and markets SSD performance enhancement solutions

Doug Dumitru, EasyCoIt would appear that you could build an all-SSD array by simply replacing all of the HDDs in a cabinet with SSDs.  I tried that and ran into some surprising issues that were very confusing at first.

SSD spec sheets, might lead you to believe that power is just not an issue.  For example, Samsung lists the power use for a 512GB 830 SSD at 0.127W (typical) for “Active Power Use”.  This implies very low demands on the system power supply.

If you do some more research, you find that the peak power usage is a lot higher.  AnandTech, in a review article reports sequential write power draw at 5.14W and random write power draw at 5.8W. In that 2.5” SSDs use the 5V power rail exclusively, this is more than Continue reading

A New Way to Use SSDs

Micron's View of Computing - Speaker is the CPU, Audience is StorageIn his Flash Memory Summit keynote on Wednesday, Micron VP and Chief Memory Systems Architect Ed Doller made a compelling demonstration of the power and performance advantages of a new approach to computing.

With true showmanship, Doller had his co-workers hand out buttons with LED lights to the entire audience.  The LEDs in these buttons were either green or blue, with the colors randomly dispersed among the crowd.  Doller asked the entire audience to turn on their lights, then called one row of the audience to file up to the stage so he could determine whether each person’s button was blue or green.

He pointed out that this was like having a single CPU check the contents of a drive.  He then asked why things should work this way – wouldn’t it be more sensible to Continue reading

Diablo: Flash Belongs on the Bus

Diablo TechnologiesDiablo Technology has just introduced a new set of DIMMs that put flash memory right onto the DDR3 memory bus.

I can already hear readers saying: “Wait!  You can’t do that!”  Well, you’re right, but the new module comes awfully close to that by putting the NAND behind an ASIC that interfaces between the DDR3 bus and the NAND.

Why do this?  Quite simply because you can get more “Bang for the Buck” by adding NAND to the system once you’ve reached a certain DRAM size.  The Diablo “Memory Channel Storage” (MCS) approach supports the addition of terabytes of NAND at the loss of Continue reading

Webinar: Flash Best Practices

I had the opportunity to participate in a round table webinar covering the best practices for solid state storage on July 18.  The hour-long session (including Q&A) can be replayed at BrightTalk.

In this round table webinar entitled Best Practices for Solid State Storage Implementation storage analyst Tom Coughlin moderated three of us, Radoslav Danilak of Skyera, Esther Spanjer of SMART Storage Solutions, and The SSD Guy (Yours Truly) in a Continue reading

Kaminario’s Performance and 7-Year Flash Life Warranties

Kaminario LogoToday Kaminario added a performance guarantee and a 7-year warranty to its arsenal.  The company introduced its “Consistency Under Failure Guarantee” which ensures customers will see no more than a 25% drop in performance during a system failure.  This means that critical operations and applications can continue to run at near-standard performance despite the failure of an SSD or even an entire node.  Kaminario president Dani Golan told The SSD Guy last week that this is a conservative guarantee, and that few customers see more than a 10% degradation during failure tests in their own production systems.

As for the 7-year flash endurance warranty, no matter which SSD Continue reading