[Beowulf] SSDs for HPC?

[Lux, Jim (337C)]

On 4/7/14 12:11 PM, "Lockwood, Glenn" <glock at sdsc.edu> wrote:

>On Apr 7, 2014, at 11:53 AM, Prentice Bisbal
><prentice.bisbal at rutgers.edu> wrote:
>
>> 4. SSDs wearing out. Is that still a concern, or are lifespans getting
>>better?I think Jim Lux once did calculations on that list to show that
>>with wear-leveling and everything else, even if you wrote to an SSD
>>constantly, it would still outlive the average lifespan of a cluster.
>
>As long as you use enterprise-grade SSDs (e.g., Intel's stuff) with
>overprovisioning, the nand endurance shouldn't be an issue over the
>lifetime of a cluster.  We've used SSDs as our nodes' system disks for a
>few years now (going on four with our oldest, 324-node production
>system), and there have been no major problems.  The major problems
>happened when we were using the cheaper commodity SSDs.  Don't give in to
>the temptation to save a few pennies there.
>
Was it wear out, or some other failure mode?

And if wear out, was it because consumer SSDs have lame leveling or
something like that?

>