From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263734AbTLYUXV (ORCPT ); Thu, 25 Dec 2003 15:23:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263800AbTLYUXU (ORCPT ); Thu, 25 Dec 2003 15:23:20 -0500 Received: from rwcrmhc11.comcast.net ([204.127.198.35]:38641 "EHLO rwcrmhc11.comcast.net") by vger.kernel.org with ESMTP id S263734AbTLYUXJ (ORCPT ); Thu, 25 Dec 2003 15:23:09 -0500 Subject: Re: 2.6.0 "Losing too many ticks!" From: Albert Cahalan To: Giacomo Di Ciocco Cc: joe.korty@ccur.com, Albert Cahalan , linux-kernel mailing list , wli@holomorphy.com In-Reply-To: <3FEB28F1.80305@nectarine.info> References: <1072321519.1742.328.camel@cube> <20031225161748.GA31564@tsunami.ccur.com> <3FEB28F1.80305@nectarine.info> Content-Type: text/plain Organization: Message-Id: <1072375533.1743.344.camel@cube> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.2.4 Date: 25 Dec 2003 13:05:34 -0500 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2003-12-25 at 13:14, Giacomo Di Ciocco wrote: > Joe Korty wrote: > > > Or maybe IDE DMA is disabled. That would account for lost > > ticks during period of heavy disk IO. Giacomo, type > > > > hdparm /dev/hda > > > > If it shows 'using DMA' off, try > > > > hdparm -d1 /dev/hda > > > > If that fails then the IDE driver you need is not > > configured in your kernel. > > > > Joe > > Hi Joe, > enabling the dma mode has resolved the "Losing too many ticks" thing, now the > system seems running fine, OK. So DMA must be on when HZ is 1000. Let's have the kernel refuse to load the IDE driver w/o DMA if HZ is over 100. Ha, ha, only serious... :-( > the unique strange thing is the "Unknown HZ value! > (92) Assume 100." message, that appears before the output of any program launched. Your clock is screwed. Reboot, or upgrade procps to a version that can compensate. Version 3.1.15 from http://procps.sf.net/ is best. Here's the release notes: ------------------------------------------------ [ANNOUNCE] procps 3.1.15 This release supports the NSA's high-security SELinux on the 2.6.0 kernel, without any additional libraries required. Thread support no longer sets off chkrootkit on buggy 2.4.xx kernels. (the PID 0 problem) Now "top" works on terminals with auto-margin problems. For those of you still upgrading from procps 2.0.xx releases, you can expect: * ps fully supports thread display (H, -L, m, -m, and -T) * ps can display NSA SELinux security contexts * top can show CPU usage for IO-wait, IRQ, and softirq * can set $PS_FORMAT to choose your own default ps format * better width control ("ps -o pid,wchan:42,args") * width of ps PID column adjusts to your system * vmstat lets you choose units you like: 1000, 1024, 1000000... * top can sort by any column (old sort keys available too) * top can select a single user to display * top can be put in multi-window mode and/or color mode * vmstat has the -s option, as found on UNIX and BSD systems * vmstat has the -f option, as found on UNIX and BSD systems * watch doesn't eat the first blank line by mistake * vmstat uses a fast O(1) algorithm on 2.5.xx kernels * pmap command is SunOS-compatible * vmstat shows IO-wait time * pgrep and pkill can find the oldest matching process * sysctl handles the Linux 2.5.xx VLAN interfaces * ps has a new "-F" format (very nice, like DYNIX/ptx has) * ps with proper BSD process selection * better handling of very long uptimes There's a procps-feedback@lists.sf.net mailing list you can use for feature requests, bug reports, and so on. Use it! Feedback makes things happen. http://procps.sf.net/ http://procps.sf.net/procps-3.1.15.tar.gz ------------- recent changes ------------- procps-3.1.14 --> procps-3.1.15 hide kernel PID bug (Linux 2.4.13-pre1 to 2.4.MAX) #217278 #219730 #217525 #224470 ps: faster threaded display top: auto-margin problem #217559 ps: support NSA SELinux, all builds, Linux 2.6+ #193648 sysctl: tweak man page for ESR's broken parser procps-3.1.13 --> procps-3.1.14 top: displays on more genuine serial terminals handle 32-bit dev_t of Linux 2.6 ps: finally, m and -m satisfy the original design ps: distinct per-thread and whole-process pending signals procps-3.1.12 --> procps-3.1.13 ps: can display NPTL threads w/ kernel patch no seLinux for now (new kernel interface) procps-3.1.11 --> procps-3.1.12 ps: explicit width ("ps -o pid,wchan:42,args") ps: $PS_FORMAT works properly #201575 top: new Linux 2.6.0-test4 CPU stats shown top: multiple -p options work again top: fixed 4 GB wrap-around ps: has a set of tests to ensure correctness man page: /var/run/utmp, not /etc/utmp #206583 required flags moved out of CFLAGS #205429 RPM generation handles /lib64 WCHAN skips leading '.' vmstat: numerous new features procps-3.1.10 --> procps-3.1.11 compile with gcc 2.95 again (C99 issue) procps-3.1.9 --> procps-3.1.10 handle GPLONLY_ symbols #143549 #188374 kill: better man page skill: better man page ps: PID-like columns change width as needed top: COMMAND instead of Command vmstat: -m displays slabinfo vmstat: -d displays disk stats ------------------------------------------------------------