9fans archive / 2008 / 09 / 147 /    prev next

From: Christian Kellermann <Christian.Kellermann@nef...>
Subject: Re: [9fans] 9p over high-latency
Date: Thu, 18 Sep 2008 12:36:31 +0200

* sqweek <sqweek@gma...> [080918 12:02]:
> On Fri, Sep 12, 2008 at 7:47 PM, erik quanstrom <quanstro@qua...> wrote:
> > as an aside: i don't think 9p itself limits plan 9 performance
> > over high-latency links.  the limitations have more to do with
> > the number of outstanding messages, which is 1 in the mnt
> > driver.
> 
>  Hm, but what's the alternative here? Readahead seems somewhat
> attractive, if difficult (I worry about blocking reads and timing
> sensitive file systems). But there's one problem I can't resolve - how
> do you know what offset to Tread without consulting the previous
> Rread's count?
>  Actually, I understand there has been discussion about grouping tags
> to allow for things like Twalk/Topen batching without waiting for
> Rwalk (which sounds like a great idea), maybe that would work here
> also...

There are some interesting approaches which have been discussed at the last iwp9, including op from nemo's team.
http://plan9.bell-labs.com/iwp9/papers/10.op.esoriano.pdf

Maybe that is worth looking at for your issue?

Kind regards,

Christian

-- 
You may use my gpg key for replies:
pub  1024D/47F79788 2005/02/02 Christian Kellermann (C-Keen)