On Wed, Jun 11, 2008 at 10:35 AM, Bob Friesenhahn
<[EMAIL PROTECTED]> wrote:
> On Wed, 11 Jun 2008, Al Hopper wrote:
>>
>> disk drives. But - based on personal observation - there is a lot of
>> hype surrounding SSD reliability. Obviously the *promise* of this
>> technology is higher performance and *reliability* with lower power
>> requirements due to no (mechanical) moving parts. But... if you look
>> broadly at the current SSD product offerings, you see: a) lower than
>> expected performance - particularly in regard to write IOPS (I/O Ops
>> per Second) and b) warranty periods that are typically 1 year - with
>> the (currently rare) exception of products that are offered with a 5
>> year warranty.
>
> Other than the fact that SSDs eventually wear out from use, SSDs are no
> different from any other electronic device in that the number of individual
> parts, and the individual reliability of those parts, results in an overall
> reliability factor for the subsystem comprised of those parts. SSDs are
> jam-packed with parts. In fact, if you were to look inside an SSD and then
> look at how typical computers are implemented these days, you will see that
> one SSD has a whole lot more complex parts than the rest of the computer.
Agreed - but the effect on overall system reliability is dominated by
the required number of interconnections (soldered joints etc), rather
than the total number of parts. But we're drifting OT here...
> SSDs will naturally become more reliable as their parts count is reduced due
> to higher integration and product maturity. Large SSD storage capacity
> requires more parts so large storage devices have less relability than
> smaller devices comprised of similar parts.
Again - agreed - but the root "problem" being addressed is the
reduction in the number of *interconnections* - which is directly
related to the number of parts.
> SSDs are good for laptop reliability since hard drives tend to fail with
> high shock levels and laptops are often severely abused.
My personal experience, echoed by numereous others I've talked with,
is that a typical laptop drive dies in 18 months - whether the laptop
travels or stays fixed on a desktop with occasional travel, for
example, in the office all week and brought home for the weekend. For
most laptops, the real enemy of laptop disk drive reliability is the
operation of the drive at elevated temperatures common inside a laptop
- rather than vibration/shock. I don't remember the number - but a
vast number of laptops spend the vast majority of their time "glued"
to a desk.
Regards,
--
Al Hopper Logical Approach Inc,Plano,TX [EMAIL PROTECTED]
Voice: 972.379.2133 Timezone: US CDT
OpenSolaris Governing Board (OGB) Member - Apr 2005 to Mar 2007
http://www.opensolaris.org/os/community/ogb/ogb_2005-2007/
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