[Dovecot] SSD drives are really fast running Dovecot

[Steve]

-------- Original-Nachricht --------
> Datum: Thu, 13 Jan 2011 10:17:20 +0100
> Von: "Miha Vrhovnik" <miha.vrhovnik at cordia.si>
> An: dovecot at dovecot.org
> Betreff: Re: [Dovecot]	SSD drives are really fast running Dovecot

> >"As a sanity check - I found some data from Mtron (one of the few SSD
> oems who
> >do quote endurance in a way that non specialists can understand). In the
> data
> >sheet for their 32G product - which incidentally has 5 million cycles
> write
> >endurance - they quote the write endurance for the disk as "greater than
> 85
> >years assuming 100G / day erase/write cycles" - which involves
> overwriting the
> >disk 3 times a day."
> >
> >That was written in 2007.  SSD flash cell life has increased
> substantially in
> >the 3-4 year period since.
> Stan you are wrong on that...
> flash cell life decreases when they shrink process in which they are made.
> 
> With the new generation of 25nm flash it's down to 3000/programming
> cycles. So the drive manufactures have to battle that with increasing a ECC
> length and better wear leaving. Or if I quote anand
> "When I first started reviewing SSDs IMFT was shipping 50nm MLC NAND rated
> at 10,000 program/erase cycles per cell. As I mentioned in a recent SSD
> article, the move to 3xnm cut that endurance rating in half. Current NAND
> shipping in SSDs can only last half as long, or approximately 5,000
> program/erase cycles per cell. Things aren’t looking any better for 25nm. Although
> the first 25nm MLC test parts could only manage 1,000 P/E cycles, today
> 25nm MLC NAND is good for around 3,000 program/erase cycles per cell.
> 
> The reduction in P/E cycles is directly related to the physics of
> shrinking these NAND cells; the smaller they get, the faster they deteriorate with
> each write."
> 
I would not use MLC in a server environment. SLC has much better program/erase cycles per cell.


> Please read the article on annandtech [1]
> 
> 1 -
> http://www.anandtech.com/show/4043/micron-announces-clearnand-25nm-with-ecc
> 
> Regards,
> Miha   

-- 
NEU: FreePhone - kostenlos mobil telefonieren und surfen!			
Jetzt informieren: http://www.gmx.net/de/go/freephone