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AC-88U 384.10_2 CPU usage discrepancies

Discussion in 'Asuswrt-Merlin' started by cyph, Apr 26, 2019.

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  1. cyph

    cyph Occasional Visitor

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    I have a question regarding the CPU usage. In the Merlin GUI, it shows the CPU as pegging at 98-99% constantly. However, using top command from SSH, CPU is pegged at 50-55%.

    I also noticed that when I reboot the router, the GUI will show CPU usage between 50-80%. However, after a day it's always showing 95%+ constantly. However, top tells a different story. Bug or working as intended?
     
  2. RMerlin

    RMerlin Super Moderator

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    Look at the top (...) of the top output. Some CPU usage comes from sirq, I/O, etc...
     
  3. cyph

    cyph Occasional Visitor

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    [​IMG]

    Using H to switch between CPU's they are all in the 50% range.

    Also, here is the CPU usage when it first start up:
    [​IMG]

    After about a day, the CPU is constantly pegged at 98%.

    Also this is the temperature with the CPU not pegged at max:
    [​IMG]

    Once CPU is pegged at 98%, the temperature jumps to 184 F constant.
     
  4. cyph

    cyph Occasional Visitor

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    This is the top CPU usage when router first start up. It appears to be about 50% of what the ASUS GUI reports:
    [​IMG]
     
  5. RMerlin

    RMerlin Super Moderator

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    No, the webui is accurate. 36% of one core + 70% of a second core roughly equals 50% of TWO cores.

    36/100 + 70/100 = 106/200
     
  6. ItsMeDude

    ItsMeDude Occasional Visitor

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    Are you using WTFast? I tried it out for a few min when I first got my router, and noticed very heavy CPU usage while it was enabled. At least one core was pegged at 100% utilization while the others bounced all over the place at a min of ~50%. As soon as I disabled it everything went back to normal. I have the AX88U, and it was all four cores.
     
  7. cyph

    cyph Occasional Visitor

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    [​IMG]

    Three hours later, the CPU is ow pegged at 95-98% constant. After reboot, the CPU process goes up and down normally. I haven't enabled anything extra since reboot. Something is causing the CPU to go into overdrive after a few hours. Temperature is now at 192 F.

    Edit: Also notice how the graph doesn't have any information before. It think the temperature just spiked when it didn't. After reboot the graph was normal.
     
  8. cyph

    cyph Occasional Visitor

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    No I didn't enable that. I did enable AIProtection. I may disable that and see if it helps. What I don't understand is this only happens after a few hours. It's normal for the first few hours after reboot.
     
  9. ItsMeDude

    ItsMeDude Occasional Visitor

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    Ah OK. I thought it was worth a shot. I'm sorry that it didn't help you.

    Good luck finding what is causing it. That would drive me crazy until I got it fixed.
     
  10. cyph

    cyph Occasional Visitor

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    Well, I think I resolved the issue but I have no idea which of the changes fixed it.

    I uninstalled spdMerlin and ntpMerlin NTP daemon. I can't say for sure that either caused it but it's 4 hours later and the CPU spike no longer occurs.
     
  11. wizin

    wizin Regular Contributor

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  12. cyph

    cyph Occasional Visitor

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  13. cyph

    cyph Occasional Visitor

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    I just turned off AIProtection. This is what my CPU looks like now on reboot:
    [​IMG]

    This is with diversion, Skynet, stubby DNS, and Yazfi running. Will update if this issue is resolved or it returns.
     
  14. el pescador

    el pescador Senior Member

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    had this last week and had been happening anytime i put diversion on.

    you have to start again.

    format usb in ext 4 format.
    then re format the jffs on next boot.

    there is a thread lurking about about how to install amtm....
     
  15. cyph

    cyph Occasional Visitor

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    It's already in ext 4. You're saying I have to reformat jffs to get rid of this issue?

    I've installed diversion via amtm.
     
  16. dave14305

    dave14305 Very Senior Member

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    There have been issues with Diversion trying to process the ash_history file if it's corrupted and consuming CPU. Since in your original screenshot there is a diversion script at the top of the list, I wonder if this is the same issue. If that top process has ash_history on the far right next time, try removing the offending file (rm /tmp/home/root/.ash_history).
     
  17. el pescador

    el pescador Senior Member

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  18. cyph

    cyph Occasional Visitor

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  19. cyph

    cyph Occasional Visitor

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    Update. Ever since I turned of AI Protection and diversion, reboot, turned diversion back on, tested it, and then turned on AI Protection, everything is back to normal again.
     
    wizin likes this.
  20. wizin

    wizin Regular Contributor

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    Yes, likewise - thanks