From owner-freebsd-net@FreeBSD.ORG Sat Oct 18 22:38:05 2008 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id F082A106568C for ; Sat, 18 Oct 2008 22:38:05 +0000 (UTC) (envelope-from sandiegobiker@gmail.com) Received: from rv-out-0506.google.com (rv-out-0506.google.com [209.85.198.229]) by mx1.freebsd.org (Postfix) with ESMTP id C6A4B8FC18 for ; Sat, 18 Oct 2008 22:38:05 +0000 (UTC) (envelope-from sandiegobiker@gmail.com) Received: by rv-out-0506.google.com with SMTP id b25so1032955rvf.43 for ; Sat, 18 Oct 2008 15:38:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to :subject:mime-version:content-type:content-transfer-encoding :content-disposition; bh=OmN92IPLSaKraSkwdk84BNm8vs4peCuwVWFpBE7vkNQ=; b=tsTKxDhpAKYIqI47gIV0yGxPsRMudoBtuPVFenXgxWnnPmg99e38ZiyQs9uGIEZZg7 ML8y2udPGqipwYmyLunPx/X4pIhkfqbHJz0Y1DGPYUaz+hflKySx5Hp9nycAI3T7ixab 7zIuW97HQcK0L6AgpeQpVpnoi7Bo9t8re3U5A= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:mime-version:content-type :content-transfer-encoding:content-disposition; b=EyqRVAfXydY8g/ZJJgv2GjfDXAGGYN+jndjX6jm1EJqtFLRh2vTH9fqzjvTuSlVyw4 y3BHydbPTsZaljxGiBakoEHUUeRxgZfb9eKFlqeM5jP7o3Z6Galrd9aMzUB1LcDn5/ET 61k8IUMTigf6ry3xlDmvbwTBBDMDNmmHG6ET8= Received: by 10.141.29.18 with SMTP id g18mr3566760rvj.298.1224367938363; Sat, 18 Oct 2008 15:12:18 -0700 (PDT) Received: by 10.141.37.19 with HTTP; Sat, 18 Oct 2008 15:12:18 -0700 (PDT) Message-ID: <27cb3ada0810181512qeab4020g912096848212ad86@mail.gmail.com> Date: Sat, 18 Oct 2008 15:12:18 -0700 From: "Len Gross" To: "freebsd-net@freebsd.org" MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline Subject: Timers in drivers vs userland X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 18 Oct 2008 22:38:06 -0000 If I place a timer directly in a driver (like Ethernet) will it be subject to less jitter and more consistency than if it were in Userland? I know FreeBSD is not "real time," but I need to be able to run a polling algorithm with about 1 ms accuracy. Thanks in advance. (Please tell me if there is a better list for this question.) -- Len