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From: "O'Connor, Daniel" <darius@dons.net.au>
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To: Xin Li <delphij@delphij.net>
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Cc: "freebsd-hackers@freebsd.org" <freebsd-hackers@freebsd.org>,
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> On 27 Mar 2015, at 14:08, Xin Li <delphij@delphij.net> wrote:
> On 3/26/15 17:58, Adrian Chadd wrote:
>> ... all the talk about this stuff, and yet noone's talked about
>> how ZFS is supposed to be append only, and boy wouldn't that be
>> awesome. :)
>=20
> It doesn't overwrite existing data with the assumption that a, let's
> say, 4K-native drive doesn't have a 1MB "band" when writing.
>=20
> I hope the "journal" would be helpful for this assuming it is on
> non-volatile medium...

The journal for the existing drives appears to be on the actual platter =
(but not shingled obviously).
This gives from pretty suboptimal write latency as you can probably =
imagine..

--
Daniel O'Connor
"The nice thing about standards is that there
are so many of them to choose from."
 -- Andrew Tanenbaum
GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C