On Thu, 11 Feb 2010, John Jason Jordan wrote: > Date: Thu, 11 Feb 2010 19:19:36 -0800 > From: John Jason Jordan <[email protected]> > Reply-To: "General Linux/UNIX discussion and help; civil and on-topic" > <[email protected]> > To: PLUG <[email protected]> > Subject: [PLUG] Top is lying > > And so is System Monitor. > > Something is eating 100% of one of my CPUs on my Fedora 11 x86_64 > Thinkpad. Occasionally it drops down, at which point the other CPU > surges to 100%. (I think they switch back and forth, probably so one of > them doesn't get too tired and go on strike.) > > System Monitor shows nothing taking more than a couple percent of > either CPU. From the command line top also shows nothing. > > Are there other tools to sleuth this down? Commands I could use? > _______________________________________________ > PLUG mailing list > [email protected] > http://lists.pdxlinux.org/mailman/listinfo/plug
I've seen this kind of thing before. Where have I seen it? On an Oracle database server that was attached to a NAS via NFS. The NFS traffic was voluminous, and it used up some serious CPU. But it didn't show up as a userland process because it was all happening in the kernel. Top does not show you an individual process for kernel work unless there's some userland connector process which is doing the heavy lifting. So think about what you might be doing with your computer that is exclusively working the kernel. Carlos _______________________________________________ PLUG mailing list [email protected] http://lists.pdxlinux.org/mailman/listinfo/plug
