Description of problem: The sysstat's programs such as mpstat shows one extra cpu. According to the result of mpstat, the number of CPU is displayed from 0 to 8. However, the number of CPU's core is actually 8, and it should be displayed from 0 to 7. > # mpstat -P ALL 1 > > 16時49分08秒 CPU %user %nice %sys %iowait %irq %soft %steal %idle intr/s > 16時49分09秒 all 0.00 0.00 0.12 0.12 0.00 0.00 0.00 99.75 6.00 > 16時49分09秒 0 0.00 0.00 0.00 1.00 0.00 0.00 0.00 99.00 0.00 > 16時49分09秒 1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.00 0.00 > 16時49分09秒 2 0.00 0.00 0.00 0.00 0.99 0.00 0.00 99.01 1.00 > 16時49分09秒 3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.00 1.00 > 16時49分09秒 4 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.00 0.00 > 16時49分09秒 5 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.00 2.00 > 16時49分09秒 6 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.00 0.00 > 16時49分09秒 7 0.00 0.00 0.99 0.00 0.00 0.00 0.00 99.01 2.00 > 16時49分09秒 8 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Additional info: In reviewing the source, when sysfs is mounted /sys, mpstat calculates the number of CPU by counting "cpu*" under /sys/devices/system/cpu/. The following in customer's environment. > # find /sys/devices/system/cpu/ -maxdepth 1 > /sys/devices/system/cpu/ > /sys/devices/system/cpu/sched_mc_power_savings > /sys/devices/system/cpu/cpuidle > /sys/devices/system/cpu/cpu0 > /sys/devices/system/cpu/cpu1 > /sys/devices/system/cpu/cpu2 > /sys/devices/system/cpu/cpu3 > /sys/devices/system/cpu/cpu4 > /sys/devices/system/cpu/cpu5 > /sys/devices/system/cpu/cpu6 > /sys/devices/system/cpu/cpu7 I assume that "cpuidle" was considered with the 9th CPU by mistake. The same phenomenon has been reported in the following issue: * https://bugzilla.redhat.com/show_bug.cgi?id=442801
Created attachment 412947 [details] Patch adapted from BZ 442801 for sysstat 7.0.2
Technical note added. If any revisions are required, please edit the "Technical Notes" field accordingly. All revisions will be proofread by the Engineering Content Services team. New Contents: Previously, the mpstat utility wrongly interpreted data about processors in the system. Consequently, it reported a processor that did not exist. This bug has been fixed and non-existent CPUs are no longer reported by mpstat.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2011-1005.html