From owner-freebsd-questions Wed Feb 14 8:50:12 2001 Delivered-To: freebsd-questions@freebsd.org Received: from be-well.ilk.org (lowellg.ne.mediaone.net [24.147.184.128]) by hub.freebsd.org (Postfix) with ESMTP id 5F95B37B491 for ; Wed, 14 Feb 2001 08:50:10 -0800 (PST) Received: (from lowell@localhost) by be-well.ilk.org (8.11.2/8.11.2) id f1EGo8700760; Wed, 14 Feb 2001 11:50:08 -0500 (EST) (envelope-from lowell) To: freebsd-questions@freebsd.org Subject: tx underrun Re: (none) References: <200102131639.f1DGdWj14713@cwsys.cwsent.com> From: Lowell Gilbert Date: 14 Feb 2001 11:50:08 -0500 In-Reply-To: Cy.Schubert@uumail.gov.bc.ca's message of "13 Feb 2001 17:40:33 +0100" Message-ID: <44bss5qke7.fsf@lowellg.ne.mediaone.net> Lines: 21 X-Mailer: Gnus v5.7/Emacs 20.7 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Cy.Schubert@uumail.gov.bc.ca (Cy Schubert - ITSD Open Systems Group) writes: > I came into work this morning and notice the following in my xconsole: > > xl0: transmission error: 90 > xl0: tx underrun, increasing tx start threshold to 120 bytes > > What would cause a tx underrun? The only cause of any large amount of > traffic from my desktop system was a Veritas backup. A tx underrun is caused by the computer not keeping up with the NIC rather than the other way around, so it's basically a question of what was keeping the computer from servicing the buffer-empty interrupts. Any other interrupt that took too long being serviced could do that, so it's hard to say what caused it in this case. A tx underrun is not in itself a problem, however. The messages are important because they may help sometimes in tracking down other problems, but a single underrun, which doesn't repeat with a larger transmit buffer, is nothing to be concerned over. It's virtually unavoidable on slower PCs, depending on the type of NIC. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message