From owner-freebsd-hackers Fri Dec 8 10:32:27 1995 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.3/8.7.3) id KAA00995 for hackers-outgoing; Fri, 8 Dec 1995 10:32:27 -0800 (PST) Received: from rocky.sri.MT.net (rocky.sri.MT.net [204.182.243.10]) by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id KAA00979 for ; Fri, 8 Dec 1995 10:32:21 -0800 (PST) Received: (from nate@localhost) by rocky.sri.MT.net (8.6.12/8.6.12) id LAA00699; Fri, 8 Dec 1995 11:34:44 -0700 Date: Fri, 8 Dec 1995 11:34:44 -0700 From: Nate Williams Message-Id: <199512081834.LAA00699@rocky.sri.MT.net> To: "Jordan K. Hubbard" Cc: "Michael C. Newell" , Joe Greco , Angelo Turetta , freebsd-hackers@freebsd.org Subject: Re: User space PPP & leased line In-Reply-To: <28835.818443536@time.cdrom.com> References: <28835.818443536@time.cdrom.com> Sender: owner-hackers@freebsd.org Precedence: bulk > > One thing we DID notice was that the transfer speeds using the user mode > > code were SIGNIFICANTLY higher than those using the kernel mode code - > > for example, transferring a medium size binary file (one that could be > > fully transferred in < 2 minutes :-) using pppd takes an average of > > 2.3KB/s whereas with ijppp it's more like 3.3KB/s (using a V.fc modem > > connection at 26.4Kb/s). I'm not sure why this should be, but given the > > That's also worth investigating. I can't see any inefficiency that > should result in *that* much slowdown, and my own tests showed > virtually no difference between the two In a word, 'Predictor-1 compression'. It's available on ijppp, and not with kernel-mode ppp and makes a significant difference. Nate