Rob,
1) I did a little digging.
Enterprise Multi-Level Cell (eMLC) flash memory blends enterprise-class
performance and reliability characteristics with the more cost-effective
characteristics of MLC flash storage. The new third-generation SSD builds upon
this base and, using advances in both the SSD device controller flash memory
management plus advances in MLC technology itself, offer an even better value
proposition. Like IBM's earlier eMLC SSDs, the drives are designed to deliver great
sustained performance levels and extended endurance and reliability. For example,
the new eMLC SSD modules were designed to provide 24x7x365 usage even running
write-intensive levels for about five years. Typical client usage is expected to be
much lower, especially regarding the average percentage of writes, and thus drive
life span can be much longer.
2) Are you sure about the 1 year warranty. My BP sold us our recent 775 SSD disk swap with a 3 year maintenance cost savings.
I'm reconfirming the warranty period.
3) What I found on warranty period is the smaller systems have a 3 year and the large systems a 1 year.
So the same SSD drive could either have a 3 year or 1 year warranty, depending on the system.
Warranty period
These features assume the same warranty or maintenance terms as the machine in
which they are installed for the full warranty or maintenance period announced for
such machine.
Flash memory cells have a maximum number of program/erase cycles. IBM Flash
Adapter 90 failures will be replaced during the standard warranty period for the
attached server at IBM's expense regardless of usage levels. IBM Maintenance
Agreements after the warranty period are limited to adapters that have not reached
the maximum number of program/erase cycles. Adapters that reach this limit
may fail to operate according to specifications and must be replaced at customers
expense.
IBM Flash Adapter 90: Typical service life is expected to exceed five years. Individual
service life may vary and can be monitored using an OS command
Paul
-----Original Message-----
From: MIDRANGE-L [mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of rob@xxxxxxxxx
Sent: Tuesday, August 04, 2015 11:09 AM
To: Midrange Systems Technical Discussion
Subject: RE: SSD performance article
<snip>
Is there an indicator or something to tell you how much life is left on an SSD?
</snip>
Good question. STRSST does have some nice stuff in there for cache batteries and the like. IDK if there's any such area for SSD's
<snip>
How does one even attempt to predict SSD life expectancy?
</snip>
I can imagine IBM would be happy to tell you that. The problem is that it would involve gathering so much statistical data and some complicated math that in the end you'll abandon the project. And they will still cover themselves with disclaimers that any fluctuation in workload and whatnot will change the outcome.
Rob Berendt
--
IBM Certified System Administrator - IBM i 6.1 Group Dekko Dept 1600 Mail to: 2505 Dekko Drive
Garrett, IN 46738
Ship to: Dock 108
6928N 400E
Kendallville, IN 46755
http://www.dekko.com
From: "Steinmetz, Paul" <PSteinmetz@xxxxxxxxxx>
To: "'Midrange Systems Technical Discussion'"
<midrange-l@xxxxxxxxxxxx>
Date: 08/04/2015 10:21 AM
Subject: RE: SSD performance article
Sent by: "MIDRANGE-L" <midrange-l-bounces@xxxxxxxxxxxx>
Larry / Rob,
Is there an indicator or something to tell you how much life is left on an
SSD?
How does one even attempt to predict SSD life expectancy?
So writes, updates, deletes will reduce life expectancy.
Reads are fine?
Rob, your Power8 SSD are only about a year old.
Do you think they failed due to EOL or other failure?
Back in Feb, 2015 I replaced 18 177gb SSD (3 + years with no failures)
with 13 775gb for space reasons and maintenance savings.
Never realized I was also renewing my SSD life expectancy at the same
time.
Correct me if I'm wrong, the SSD come with a 3 year warranty, SSD
maintenance kicks in starting in year 4.
Paul
-----Original Message-----
From: MIDRANGE-L [mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of
rob@xxxxxxxxx
Sent: Tuesday, August 04, 2015 10:02 AM
To: Midrange Systems Technical Discussion
Subject: RE: SSD performance article
<snip>
So what would be the normal life expectancy for a SSD, 3, 5, 10 years?
</snip>
I think that would depend on writes. IOW, YMMV. Try a never ending
repetition of CRTNWSSTG followed by DLTNWSSTG if you really want to put it
through the paces.
IBM curtails certain commands from working on SSD's to keep yourself from
shooting yourself in the foot. Like STRASPBAL *USAGE, STRDSKRGZ, etc.
I have three Power 8's. Each one has lost at least one drive. Two of the
three are running SSD's. I'm a big fan of Raid 5 with hot spare. Sure,
there some naysayers that say RAID5 and RAID6 are both obsolete due to
disk size, etc. Their charts may be saying one thing, but my experience
is saying another.
Rob Berendt
--
IBM Certified System Administrator - IBM i 6.1 Group Dekko Dept 1600 Mail
to: 2505 Dekko Drive
Garrett, IN 46738
Ship to: Dock 108
6928N 400E
Kendallville, IN 46755
http://www.dekko.com
--
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