On Sat, 2011-06-04 at 01:41 -0400, Sean Breheny wrote:
> Herbert,
>=20
> How can you be sure that you will still be able to read it after it
> can no longer be written? Maybe I'm missing something about how wear
> leveling works, but it would seem to me that one could easily end up
> with changes which you tried to write but which only partially "took"
> due to some cells no longer being writable, and then the data is a
> jumbled mess of old and new. Also, it is not clear to me that the
> failure mode of flash cells is always such that data is preserved. I
> would think that excessive writes might break down the insulating
> oxide layer and cause excessive leakage current, causing failed cells
> to get stuck at a random state.

I don't know the exact mechanism of how "end of writes" happens, but
most of the reviews state that when writes are "done" you end up with a
read only drive.

Again though, think about it for a second: how many 10+ year old drives
do you care at all about accessing anymore? All the data on any drive
more then say 5 years old on any of my computers has long been moved to
bigger storage. The oldest drive in any of my devices is probably 3 or 4
years (except my satellite TV PVR, that one is probably going on 8
years).

As with anything in life, it's up to you to weigh the issues and make
choices appropriately. All my data is on a central server that is
accessed over my home network, or when away over VPN or SSH tunnels. I
always have everything backed up anyways, so if a drive in my server
goes down all my important data is safe.

For me, the price for SSD is still too high, but it's getting there.

TTYL

--=20
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