this is the home page of
leading the way to the new storage frontier .....
SSD myths - write endurance
SSD endurance ..
disk writes per day in enterprise SSDs
DWPD ....
SSD SoCs controllers
SSD controllers ....
image shows Megabyte's hot air balloon - click to read the article SSD power down architectures and acharacteristics
SSD power loss ..
image shows software factory - click to see storage software directory
SSD software ....

the limericks of flash SSD endurance

this is the true story of how a serious subject begat a bunch of rhymes and
a mention at the 2016 Flash Memory Summit (see also:- SSD market history)

There was a young lady called Prudence

Was worried 'bout flash's endurance

She met an IP

Who said - stick by me

My software will be your ensurence

(the above limerick having been inspired by reading about a company called NVMdurance)

more about a limerick concerning SSD endurance?

by Zsolt Kerekes, editor - - April 21, 2016

Last night - while not-quite watching tv - I saw (via my linkedin connections) a note by Stephen Bates at Microsemi who commented on a post by Pearse Coyle, CEO - NVMdurance who was bringing attention to an article - Memories will be made of this (published in SiliconRepublic) in which Coyle is interviewed about his own SSD software company which is in the flash endurance stretching business.

When I saw that the roots of the company lay in Limerick I was inspired to write something and I dashed off to the kitchen to make a cup of tea. And while waiting for the water to boil the complete verse just sprang out, line by line, just as you see it here above.

I had intended to write more about NVMdurance's technology at some time although this rhyme was not precisely the kind of thing I had in mind.

...Later:- in the week following the above rhyme I spoke at length to NVMdurance's CEO - Pearse Coyle - about the history of flash characterization and how it relates to endurance and controller techniques.

I said that one aspect of this reminded me of something another company had done 4 years earlier.

You can see more about this conversation in my article - relating NVMdurance's machine learning to manual tuning

Once the limerick idea got in my head. It stuck for a while. I returned to the subject soon after with this apology

Is it a crime?

That I wrote a rhyme

A diddle dee dee

About #SSD

It didn't take long

To knock out that song

I stirred it while boiling my tea

Here are some links to serious articles I've written about SSD endurance

SSD endurance myths and legends
razzle dazzling flash SSD cell care claims
adaptive R/W flash care management & DSP IP in SSDs
pre DSP era (classical) wear leveling for flash reliability

And you can see news updates on the state of the art here:- SSD controllers page

SSD ad - click for more info
more Flash Limericks at the Flash Memory Summit
Editor:- May 5, 2016 - NVMdurance today announced a Flash Memory Limerick competition the winner of which will be announced at the Flash Memory Summit.

Editor's comments:- when I saw the linkedin post about this by Aisling Foley at Aisling Foley Marketing - I couldn't stop myself thinking...

life steps imageAha! - now I know more about NVMdurance's technology and the 5 stage life cycle budget (pdf) it uses to dress the flash in a fashion which is age appropriate - how can I get that in?

The sages of flash now agree

That if you fall out of a tree

To increase your chances

Grab hold at five branches

And swing around judiciously

Editor again - I still can't decide whether "grab hold of" is better than "grab hold at".

One sounds more natural while the other sounds forced but more accurately paints the picture. But I'm not going to agonize over it any longer. And just to be clear. I myself don't enter competitions. So your field is clear (of mice anyway).
SSD ad - click for more info
there was a flash memory bard
who said it's not really that hard
playing limerick sports
takes less time than reports
as all the words fit on a card
Editor:- August 24, 2016 - In case you missed it - there were a LOT of entries in the Flash Memory Limerick competition organised by NVMdurance.

The draw winner - announced at the Flash Memory Summit - was Tom Coughlin, President Coughlin Associates.

You can read Tom's winning entry and many other fine examples from people in the SSD industry who have invented many playful ways to link the ideas of endurance, flash, SSDs and even business development themes in unique ways that have never before been seen in SSD history. all the limericks

Since 2003 MRAM vendors have been promising they will soon replace flash. But alternative nvms weren't the only threats which failed to make an appearance in the "kill flash wars".
SSD's past phantom demons