From owner-freebsd-usb@FreeBSD.ORG Sun Aug 9 17:50:29 2009 Return-Path: Delivered-To: freebsd-usb@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 8A0731065670 for ; Sun, 9 Aug 2009 17:50:29 +0000 (UTC) (envelope-from asmrookie@gmail.com) Received: from mail-fx0-f224.google.com (mail-fx0-f224.google.com [209.85.220.224]) by mx1.freebsd.org (Postfix) with ESMTP id 1879E8FC31 for ; Sun, 9 Aug 2009 17:50:28 +0000 (UTC) Received: by fxm24 with SMTP id 24so2783527fxm.36 for ; Sun, 09 Aug 2009 10:50:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to:cc :content-type:content-transfer-encoding; bh=4PJb3CGRp7Be+MLA9PXDZrBTmlFtAd02t2J9Wwd/FJ0=; b=pgqkbq+GPfhVj8lrKGx4vfho9QfOSiaoHwsJtReuLy+LPQJQ78ksrxmJbIUS5FHF64 ZvVkn4JsnVbjN+tLnPak0O9qQDtMTZzchVTZMvX04tJ0agMdgMqL5nxabe8gPG6arSi1 5oWJAtE4aaWN8aS28pq+qlONWS9pTz9psu5GE= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=HWx9JYBuNC5f4LFaWuulTOj2hTACEH65CJ1M+MHnpPwUInNJQsYJuGjJn8ABDjgEu8 tBjLeU9+C0uIfkAlANG66+AA6EtzcZipQfVHm3qTeqf0EFfAbHseuDZNOSvKV1KV/inM 6EjfVUwbrp2mE6NRfTnqlq0nspJKj1G14axlY= MIME-Version: 1.0 Sender: asmrookie@gmail.com Received: by 10.223.103.133 with SMTP id k5mr670777fao.76.1249838744916; Sun, 09 Aug 2009 10:25:44 -0700 (PDT) In-Reply-To: <20090809.105507.-646227496.imp@bsdimp.com> References: <20090809.102341.2106235641.imp@bsdimp.com> <200908091840.55000.hselasky@c2i.net> <20090809.105507.-646227496.imp@bsdimp.com> Date: Sun, 9 Aug 2009 19:25:44 +0200 X-Google-Sender-Auth: b1fa9061a8f6b444 Message-ID: <3bbf2fe10908091025t7f8d00dbw5b0589728cf400ad@mail.gmail.com> From: Attilio Rao To: "M. Warner Losh" Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: freebsd-usb@freebsd.org Subject: Re: Performance issues X-BeenThere: freebsd-usb@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: FreeBSD support for USB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 09 Aug 2009 17:50:29 -0000 2009/8/9 M. Warner Losh : > In message: <200908091840.55000.hselasky@c2i.net> > Hans Petter Selasky writes: > : On Sunday 09 August 2009 18:23:41 M. Warner Losh wrote: > : > Any ideas how to track this down? > : > : Hi, > : > : USB is only draining from "usbd_transfer_drain()" in > : /sys/dev/usb/usb_transfer.c . You could add a print including the backtrace > : and see if that function gets called when it freezes. > > Ummm. No. Adding a traceback print to a function that's called 60 > times a second in steady state doesn't seem like a viable option. > > : Else I would try to compile a fresh kernel from USB P4. There are > : some patches there in relation to the recent newbus lock change, > : that might help. > > This kernel predates the newbus lock change. > > : USB uses uppercase "WDRAIN". Is your printout lowercase "wdrain" ? > > Yes. That's used by the buffer cache in order to reduce pressure of asynchronous writes. It waits for other writes to complete before to go on. Probabilly, I/O requests get stuck for another reasong starving the asynchronous requests queue flushing. Attilio -- Peace can only be achieved by understanding - A. Einstein