I have similar symptoms. If the System Monitor window is resized to the smallest possible size, the CPU usage drops to between 7 and 10%. If i maximize the window, it quickly jumps to +60%. I have the same issue on 2 similarly configured machines, both running 8.04 beta.
The window size relationship causes me to believe the custom graphing/plotting widgets used by gnome-system-monitor are the source of the problem, but watching top, i can see it's my Xorg process that is occupying the cpu resources. Separately, the new gnome-system-monitor shows only one cpu on both my quad and dual cored systems. Is this related to the completely fair scheduler? could this be related to the bug we are seeing? Ubuntu 8.04 beta CPU: 1-2.4ghz core 2 quad 2-2.4ghz core 2 duo GPU 1-nVidia 7600 GS 2-nVidia 8800 GTS MB 1 & 2 - EVGA 122-CK-NF68-T1 Sound and Lan on board -- System monitor takes 50% CPU https://bugs.launchpad.net/bugs/202624 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
