Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 15 Dec 1998 00:23:00 +0100
From:      Poul-Henning Kamp <phk@critter.freebsd.dk>
To:        "Jonathan M. Bresler" <jmb@FreeBSD.ORG>
Cc:        johan@granlund.nu, julian@whistle.com, lars@akerlings.t.se, current@FreeBSD.ORG, isdn@FreeBSD.ORG
Subject:   Re: if_sppp is BROKEN!!! 
Message-ID:  <6841.913677780@critter.freebsd.dk>
In-Reply-To: Your message of "Mon, 14 Dec 1998 15:07:41 PST." <199812142307.PAA27390@hub.freebsd.org> 

next in thread | previous in thread | raw e-mail | index | archive | help
In message <199812142307.PAA27390@hub.freebsd.org>, "Jonathan M. Bresler" write
s:
>> Date: Mon, 14 Dec 1998 22:12:29 +0100 (CET)
>> From: Johan Granlund <johan@granlund.nu>
>> 
>> This is really interesting!
>> One of the concepts i liked in SYSV (ducking for cover) was streams and
>> its ability to chain together modules to process a datastream.
>> If it's coupled with kld to dynamically load/unload modules i think
>> you have something _very_ good.
>> 
>> That network thing. Can a module route a package thru different modules
>> based on contents and state?
>
>  the idea of streams is wonderful, the realization is costly.  each
>  layer added (or module pushed) slows down processing and hurts
>  throughput.  ritchie developed streams for serial, if i remember
>  correctly.  streams was then applied to networks.  there is an RFC
>  about layering being bad for networking and the relative performance
>  of NIT vs BPF prove the case.

But with that said, there is still something to be said for modular
and well defined interfaces.  But streams ?  No.  They were great
for async protocols, but they fail badly for packet stuff.

--
Poul-Henning Kamp             FreeBSD coreteam member
phk@FreeBSD.ORG               "Real hackers run -current on their laptop."
"ttyv0" -- What UNIX calls a $20K state-of-the-art, 3D, hi-res color terminal

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-isdn" in the body of the message



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?6841.913677780>