From owner-freebsd-hackers Thu Mar 16 12:11:00 1995 Return-Path: hackers-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.10/8.6.6) id MAA24894 for hackers-outgoing; Thu, 16 Mar 1995 12:11:00 -0800 Received: from Root.COM (implode.Root.COM [198.145.90.1]) by freefall.cdrom.com (8.6.10/8.6.6) with ESMTP id MAA24887 for ; Thu, 16 Mar 1995 12:10:58 -0800 Received: from corbin.Root.COM (corbin.Root.COM [198.145.90.18]) by Root.COM (8.6.8/8.6.5) with ESMTP id MAA14629; Thu, 16 Mar 1995 12:10:53 -0800 Received: from localhost (localhost [127.0.0.1]) by corbin.Root.COM (8.6.11/8.6.5) with SMTP id MAA00215; Thu, 16 Mar 1995 12:10:52 -0800 Message-Id: <199503162010.MAA00215@corbin.Root.COM> X-Authentication-Warning: corbin.Root.COM: Host localhost didn't use HELO protocol To: Chitra Venkatramani cc: hackers@FreeBSD.org Subject: Re: net question In-reply-to: Your message of "Thu, 16 Mar 95 10:23:03 EST." <199503161523.KAA21273@cs.sunysb.edu> From: David Greenman Reply-To: davidg@Root.COM Date: Thu, 16 Mar 1995 12:10:51 -0800 Sender: hackers-owner@FreeBSD.org Precedence: bulk > In if_ed.c, the ethernet driver, the sizes of the transmit and >receive buffers are set. For 16bit cards, the transmit buffer size >is set to 2 buffers, each 6 pages, each page being 256 bytes. >And the remaining memory is set aside for the receiver ring buffer. > >I would like to know if it is possible to set the transmit buffer >size to be larger, say 6 buffers and leave the rest for the receiver, >in software ? That is, is this parameter software configurable ? It is possible, and would require a one line patch to the driver code. It was written to support an arbitrary number of transmit buffers. I did quite a bit of testing after writing the code to determine if there was any performance difference between 2 transmit buffers and 3, 4, 5, etc. In all of my tests, the performance came out the same. I can contrive some cases where more buffers might help...but the improvement would likely be very marginal. -DG