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From: Roland Dreier <rdreier@cisco.com>
To: James Bottomley <James.Bottomley@suse.de>
Cc: Arjan van de Ven <arjan@infradead.org>,
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Subject: Re: Discard support
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 > Well, yes and no ... a lot of SSDs don't actually implement NCQ, so the
 > impact to them will be less ... although I think enterprise class SSDs
 > do implement NCQ.

Really?  Which SSDs don't implement NCQ?

It seems that one couldn't keep the flash busy doing only one command at time.