On Fri, Apr 01, 2016 at 10:28:03AM +0100, Alex Bligh wrote:
>
> On 1 Apr 2016, at 09:35, Wouter Verhelst <w...@uter.be> wrote:
>
> >> +* All write commands (that includes both `NBD_CMD_WRITE` and
> >> + `NBD_CMD_TRIM`) that the server completes (i.e. replies to)
> >> + prior to processing to a `NBD_CMD_FLUSH` MUST be written to non-volatile
> >> + storage prior to replying to that `NBD_CMD_FLUSH`. The server SHOULD
> >> ensure
> >> + that all write command received prior to processing the `NBD_CMD_FLUSH`
> >> + (whether they are replied to or not) are written to non-volatile
> >> + storage prior to processing an `NBD_CMD_FLUSH`; note this is a
> >> + stronger condition than the previous 'MUST' condition. This
> >
> > This seems to make little sense. Are you saying that suddenly now
> > sending a reply for FLUSH with outstanding writes is wrong? If not, the
> > above should be clarified.
>
> The MUST sentence does not cover that situation as it only refers
> to completed writes.
>
> The SHOULD sentence says that's a 'SHOULD NOT' situation in respect
> of writes that have PROCESSED (i.e actioned) whether or not they
> have been replied to. Of course the client has no way of knowing
> whether they have been PROCESSED without a reply.
>
> Personally I think the SHOULD clause is pretty pointless and is
> unnecessary, but that's where the conversation got to n years
> ago I believe.
I'm still not sure what it's supposed to mean, though. Clearly, you
should at the very least reword it, if not...
> Happy to delete the last sentence if that's wrong.
... remove it instead.
--
< ron> I mean, the main *practical* problem with C++, is there's like a dozen
people in the world who think they really understand all of its rules,
and pretty much all of them are just lying to themselves too.
-- #debian-devel, OFTC, 2016-02-12
