Re: Rename+crash behaviour of btrfs - nearly ext3!

[Oystein Viggen <oysteivi@tihlde.org>]

* [Chris Mason]=20

> I'm more than open to discussion on this one, but I don't see how:
>
> rm -f foo2
> dd if=3D/dev/zero of=3Dfoo bs=3D1M count=3D1000
> mv foo foo2
>
> Should be expected to write 1GB of data.

IIRC, the answer you're looking for is "it did with ext3 in the default
data=3Dordered mode".  Combine that with the ext3 data=3Dordered fsync(=
)
escalation where (again IIRC) fsync() tended to force a full sync() of
the file system, and it's not that difficult to see why someone would
program with the expectation above.

Anyway, there's still a question of if a new file system should emulate
the quirks of the old file system (read: be bug compatible), or if you
can just expect to be popular enough that userspace adapts to the new
order and lets you do The Right Thing instead.

=D8ystein
--=20
Outgoing mail is certified Virus Free.
=2E.of course, the virus would tell you the same thing..

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