Re: [9fans] Plan9 - the next 20 years

[erik quanstrom <quanstro@coraid.com>]

> I thought 9p had tagged requests so you could put many requests in flight at
> once, then synchronize on them when the server replied.
>
> Maybe i misunderstand the application of the tag field in the protocol then?
>
> Tread tag fid offset count
>
> Rread tag count data

without having the benefit of reading ken's thoughts ...

you can have 1 fd being read by 2 procs at the same time.
the only way to do this is by having multiple outstanding tags.

i think the complaint about 9p boils down to ordering.
if i want to do something like
	cd /sys/src/9/pc/ ; cat sdata.c
that's a bunch of walks and then an open and then a read.
these are done serially, and each one takes 1rtt.

- erik