From mboxrd@z Thu Jan  1 00:00:00 1970
From: erik quanstrom <quanstro@labs.coraid.com>
Date: Fri, 30 Apr 2010 12:13:59 -0400
To: 9fans@9fans.net
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Subject: Re: [9fans] A simple experiment
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> > i don't see any reason why 9p couldn't use some of the same
> > congestion control ideas.  the trick would be to feed back packet loss
> > detection and retransmission info to the point where file io gets
> > turned into rpcs→the mount driver
>
> Agreed -- sort of what I meant by "I hope 9p evolves".
> Though I'd probably stick this in a layer below 9p.

i suggested putting it above 9p.  i don't understand your
suggestion.  how would a layer below know that there is
more data?

> It can
> backpressure a 9p client if it tries to send too much (either
> by blocking or returning with equiv of EWOULDBLOCK).

isn't that what you just complained about—fcp having to
do the kernel's work?

i think EWOULDBLOCK would be a big mistake.  io
in plan 9 is synchronous.  and this is very much on purpose.

- erik