Ubuntu 16.04.3 with High CPU Load.

Asked by Kgosi Smalz on 2018-07-20

Load average spikes up on random days just after 19:00 PM in the evening and hangs the machine, but the system works fine after a restart until the issue resurfaces again.

We have created a script to track the interrupts "/sys/firmware/acpi/interrupts" when the problem occurs and we did not pick up any interrupts with high values and mostly on the invalid state.

**
/sys/firmware/acpi/interrupts/sci: 0
/sys/firmware/acpi/interrupts/error: 0
/sys/firmware/acpi/interrupts/gpe00: 0 enabled
/sys/firmware/acpi/interrupts/gpe01: 0 invalid
/sys/firmware/acpi/interrupts/gpe02: 0 invalid
/sys/firmware/acpi/interrupts/gpe03: 0 invalid
/sys/firmware/acpi/interrupts/gpe04: 0 invalid
/sys/firmware/acpi/interrupts/gpe05: 0 invalid
/sys/firmware/acpi/interrupts/gpe06: 0 invalid
/sys/firmware/acpi/interrupts/gpe07: 0 invalid
/sys/firmware/acpi/interrupts/gpe08: 0 invalid
/sys/firmware/acpi/interrupts/gpe09: 0 invalid
/sys/firmware/acpi/interrupts/gpe0A: 0 invalid
/sys/firmware/acpi/interrupts/gpe0B: 0 invalid
/sys/firmware/acpi/interrupts/gpe0C: 0 invalid
/sys/firmware/acpi/interrupts/gpe0D: 0 invalid
/sys/firmware/acpi/interrupts/gpe0E: 0 invalid
/sys/firmware/acpi/interrupts/gpe0F: 0 invalid
/sys/firmware/acpi/interrupts/sci_not: 0
/sys/firmware/acpi/interrupts/ff_pmtimer: 0 invalid
/sys/firmware/acpi/interrupts/ff_rt_clk: 0 disabled
/sys/firmware/acpi/interrupts/gpe_all: 0
/sys/firmware/acpi/interrupts/ff_gbl_lock: 0 enabled
/sys/firmware/acpi/interrupts/ff_pwr_btn: 0 invalid
/sys/firmware/acpi/interrupts/ff_slp_btn: 0 invalid
**

Upon investigation, we have noticed a lot of kworker processes on the top command.

top - 19:17:03 up 2 days, 10:54, 0 users, load average: 258.16, 243.83, 156.08
Tasks: 486 total, 2 running, 484 sleeping, 0 stopped, 0 zombie
%Cpu(s): 2.2 us, 4.4 sy, 0.0 ni, 0.0 id, 84.2 wa, 0.0 hi, 9.2 si, 0.0 st
KiB Mem : 2036616 total, 796600 free, 198248 used, 1041768 buff/cache
KiB Swap: 2093052 total, 2093052 free, 0 used. 828716 avail Mem

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
    3 root 20 0 0 0 0 S 7.8 0.0 1:29.43 ksoftirqd/0
25149 root 20 0 0 0 0 S 5.0 0.0 0:42.65 kworker/0:2+
.
.
.
18826 root 20 0 0 0 0 D 0.0 0.0 0:01.22 kworker/u12+
19471 root 20 0 0 0 0 D 0.0 0.0 0:00.40 kworker/0:1
24768 root 20 0 0 0 0 D 0.0 0.0 0:00.01 kworker/0:2
24784 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 bioset
24785 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 bioset
24787 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/0:3
24815 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/u12+
24816 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/0:4
24819 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/0:5
24821 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/0:6
24823 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/0:7
24824 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/0:8
24826 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/0:9
.
.
.
24912 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/0:53
24914 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/0:54
24916 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/0:55
24918 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/0:56
24919 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/0:57
24921 root 20 0 0 0 0 D 0.0 0.0 0:00.00 kworker/0:58

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Last query:
2018-07-20
Last reply:
2018-08-05
Launchpad Janitor (janitor) said : #2

This question was expired because it remained in the 'Open' state without activity for the last 15 days.