From mboxrd@z Thu Jan  1 00:00:00 1970
From: Vladislav Bolkhovitin <vst@vlnb.net>
Subject: Re: [sqlite] light weight write barriers
Date: Fri, 26 Oct 2012 21:55:04 -0400
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To: Theodore Ts'o <tytso@mit.edu>, Alan Cox <alan@lxorguk.ukuu.org.uk>,
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Theodore Ts'o, on 10/25/2012 09:50 AM wrote:
> Yeah....  I don't buy that.  One, flash is still too expensive.  Two,
> the capital costs to build enough Silicon foundries to replace the
> current production volume of HDD's is way too expensive for any
> company to afford (the cloud providers are buying *huge* numbers of
> HDD's) --- and that's assuming companies wouldn't chose to use those
> foundries for products with larger margins --- such as, for example,
> CPU/GPU chips. :-) And third and finally, if you study the long-term
> trends in terms of Data Retention Time (going down), Program and Read
> Disturb (going up), and Write Endurance (going down) as a function of
> feature size and/or time, you'd be wise to treat flash as nothing more
> than short-term cache, and not as a long term stable store.
>
> If end users completely give up on flash, and store all of their
> precious family pictures on flash storage, after a couple of years,
> they are likely going to be very disappointed....
>
> Speaking personally, I wouldn't want to have anything on flash for
> more than a few months at *most* before I made sure I had another copy
> saved on spinning rust platters for long-term retention.

Here I agree with you.

Vlad