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Subject: Re: SSD recommendations for ZFS cache/log
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On Nov 13, 2012, at 21:51, Stephen McKay <smckay@internode.on.net> wrote:

> [...lots of good advice about measuring, and lots of good advice about L2A=
RC...]
>=20
> I have no way to determine in advance the behaviour of an SSD on
> power failure so I assume all the ones I can afford have bad
> behaviour. :-)  I know that expensive ones contain capacitors so
> that power failures do not corrupt their contents.  By the nature
> of advertising (from which we know that any feature not excessively
> hyped must therefore not be supported), we must conclude that other
> SSDs by normal operation corrupt blocks on power failure.

If you'll pardon what may be an ignorant question, does this matter if you h=
ave your machine on a UPS, especially if you run upsmon or nut to do a grace=
ful shutdown when there are n minutes of battery remaining?

Thanks,
--=20
Chris BeHanna
chris@behanna.org=