MMCSD erase optimization not quite right?

[Poul-Henning Kamp]

--------
In message <550AA479.2020404 at FreeBSD.org>, Alexander Motin writes:

>> Also, UFS perhaps
>> shouldn't issue BIO_DELETE immediately, because the block might be
>> reused soon (I'm not sure what the right answer here is for best flash
>> performance).

If you reuse a block quickly, the BIO_DELETE is "wasted" in the sense
that the new write would do the same job, but unless you know something
about your reuse pattern that allows you to optimize this aspect,
statistically the best strategy is to BIO_DELETE as soon as possible.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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