Date: Tue, 13 Oct 1998 17:07:52 +0900 From: Kenjiro Cho <kjc@csl.sony.co.jp> To: Bruce Evans <bde@zeta.org.au> Cc: brian@Awfulhak.org, current@FreeBSD.ORG Subject: Re: Improper sharing of modem bandwidth Message-ID: <199810130807.RAA11582@hotaka.csl.sony.co.jp> In-Reply-To: Your message of "Tue, 13 Oct 1998 15:41:01 %2B1000." <199810130541.PAA12787@godzilla.zeta.org.au>
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Bruce Evans <bde@zeta.org.au> said: > Surely, once the packet queueing delay is reduced, we need to reduce > the tty delay. The current kernel doesn't have ioctls for the > buffer size but slip uses a smaller tty buffer and has a better > response time than ppp. >> User ppp is behind a _lot_ of output buffering, including (at speeds >= >> 57600 Kbps) a 4KB tty buffer (up from 2KB in FreeBSD-2.2). Perhaps the >> increase from 2KB to 4KB is especially significant when the MTU is 1500. Hmmm, when I tried, user ppp on a 200MHz PentiumPro apparently had no problem filling up 2x 57600bps with small (~100) output buffers. However, I monitored the throughput inside the ppp program and didn't directly observe the kernel buffers. --Kenjiro To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message
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