From owner-freebsd-hackers@FreeBSD.ORG Fri Jun 18 17:25:53 2004 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 589D016A4CE for ; Fri, 18 Jun 2004 17:25:53 +0000 (GMT) Received: from mail.sandvine.com (sandvine.com [199.243.201.138]) by mx1.FreeBSD.org (Postfix) with ESMTP id BCDE543D54 for ; Fri, 18 Jun 2004 17:25:52 +0000 (GMT) (envelope-from emaste@sandvine.com) Received: by mail.sandvine.com with Internet Mail Service (5.5.2657.72) id ; Fri, 18 Jun 2004 13:25:52 -0400 Message-ID: From: Ed Maste To: freebsd-hackers@freebsd.org Date: Fri, 18 Jun 2004 13:25:51 -0400 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2657.72) Content-Type: text/plain; charset="iso-8859-1" Subject: RE: memory mapped packet capturing - bpf replacement ? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 18 Jun 2004 17:25:53 -0000 Matthew Dillon wrote: > > There's no reason why the time has to be in microseconds or > even that it must be adjusted to realtime. You also do not > have to support low power modes during testing which means > that just time-stamping the packets with the TSC plus a simple > base offset to correct for variences between cpus and machines > on the network ought to be sufficient. Fair enough. In my case I didn't need the timestamp anyway so just disabling it was the least-effort way to remove the overhead. I pointed out the timestamp issue only because it will penalize BPF against a new method (that doesn't have them) more than one might expect. -ed