can a wrong alignment cause a decrease in a hdd's life expectancy?

Jeremy Chadwick freebsd at jdc.parodius.com
Mon Dec 19 23:22:18 UTC 2011


On Mon, Dec 19, 2011 at 03:20:10PM -0800, Jeremy Chadwick wrote:
> On Mon, Dec 19, 2011 at 10:56:33PM +0000, Alexander Best wrote:
> > On Mon Dec 19 11, Poul-Henning Kamp wrote:
> > > In message <20111219224700.GA75581 at freebsd.org>, Alexander Best writes:
> > > >On Mon Dec 19 11, Poul-Henning Kamp wrote:
> > > >> In message <20111219221617.GA70383 at freebsd.org>, Alexander Best writes:
> > > >> 
> > > >> >ps: the hdd only gets mounted read-only!
> > > >> 
> > > >> There is no known wear-effects in flash storage as long as you
> > > >> only read.
> > > >> 
> > > >> You may need to do refresh-writes every 5-10 years to avoid
> > > >> tunnel-leakage bit errors, but most flash controllers use semi-long
> > > >> ECC syndromes and will do so on first bit that gives an read error.
> > > >
> > > >this is a regular hdd i believe -- no ssd. at least when i plug it into my
> > > >usb drive i hear the hdd spinning up and causing vibrations. i don't think
> > > >that would be the case with an ssd.
> > > 
> > > Ahh, sorry, I don't know why I thought it was flash.
> > 
> > no problem. so will the improper alignment also not cause a life expectancy
> > shortage in case of a hdd (non-flash-based)?
> 
> The improper alignment will result in sub-par write performance, and a
> slight decrease in read performance writes -- but will not impact life
> expectancy or "harm" the drive in any way.

This should have read "...slight decrease in read performance", not
"read performance writes".  Editing mistake on my part.  :-)

-- 
| Jeremy Chadwick                                jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                   Mountain View, CA, US |
| Making life hard for others since 1977.               PGP 4BD6C0CB |



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