-------- Original Message -------- Subject: Processes causing CPU to overheat Date: Mon, 22 Aug 2005 22:11:41 +0000 From: Jon Roland <jroland at linux-migration.net> Reply-To: jroland at linux-migration.net Organization: Linux Migration Network To: sensors at stimpy.netroedge.com CC: Rob Ristroph <rgr at sdf.lonestar.org>, Les Nemeth <linuxles at yahoo.com> One of my systems, with an Athlon 64 running Fedora Core 4, has developed an interesting problem. With a temperature monitor I installed, the CPU runs at about 35 C normally, no matter what I am doing. But then, for no apparent reason, the temperature rises rapidly to about 52 C and the system freezes, or sometimes crashes. GKrellM shows a sudden rise in "nice usage" on the CPU and in both processes and disk usage at the same time. Once the rise begins, I have only seconds before the system freezes. Attached are two frames from a log of top -b -c , the first from just before the transition, the second from just after. Note the sudden appearance of ten perl processes that consume about 10% of the CPU each. I killed the first of those perl processes before the freezeup could occur, and all the perl processes also died, the nice usage dropped to zero, and the CPU temperature dropped back to the normal level of 35 C. I have since rebooted the system, but the problem, which previously occurred after about a half-hour of a session, has not returned, so far, after 10 hours. We have been trying to figure out how 100 CPU usage could cause the CPU to overheat. The only thing we can think of is that the processes might have somehow turned off power to the CPU fan, or increased power to the CPU. Have you ever encountered that kind of thing? Where it gets interesting, and why I am contacting you, is that before I killed that process, I could run sensors. Since then, when I run it, I get "No sensors found!". I ran sensors-detect, and it seems to have run okay. Log attached. This suggests to me that the process I killed has something to do with sensors. Any comments or suggestions? Please visit my website, http://www.constitution.org -- Jon http://www2.lm-sensors.nu/~lm78/support.html ---------------------------------------------------------------- Linux Migration Network 7793 Burnet Road #37, Austin, TX 78757 512/374-9585 www.linux-migration.net jroland at linux-migration.net ---------------------------------------------------------------- -------------- next part -------------- A non-text attachment was scrubbed... Name: top_050822-00x.log Type: text/x-log Size: 20728 bytes Desc: not available Url : http://lists.lm-sensors.org/pipermail/lm-sensors/attachments/20050822/997d9906/attachment.bin -------------- next part -------------- An embedded and charset-unspecified text was scrubbed... Name: 050822_sensors-detect.txt Url: http://lists.lm-sensors.org/pipermail/lm-sensors/attachments/20050822/997d9906/attachment.txt
