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Core 2 100% Utilization on 380.61 RT-AC68U

Discussion in 'Asuswrt-Merlin' started by rlfromm, Sep 13, 2016.

  1. rlfromm

    rlfromm New Around Here

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    The router is doing nothing yet Core 2 is 100% utilized. Any ideas?

    Also remote SSH does not work and remote GUI does not work. I have checked all the settings and they are set as they were when these features were working before. Any ideas?

    So I noticed the router would no reboot when requested. keep seeing message: Skip event: reboot, in the log.

    I had my wife cycle the power and now everything is OK.

    Router was up for 11 days. Memory leak of type causing my problem?
     
    Last edited: Sep 13, 2016
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  3. RMerlin

    RMerlin Super Moderator

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    Check with "top" over SSH to determine what is using the CPU.
     
  4. rlfromm

    rlfromm New Around Here

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    I could not check with top. the local SSH or telnet would not work either. I could connect but it would not take any commands.
     
  5. evh909

    evh909 Regular Contributor

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    Are you utilizing the dnla server? If so, disable it and see if your CPU usage goes down
     
  6. avi68

    avi68 Regular Contributor

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    Im having the exact same problem. I have this problem after 20 days, once the router has been running for 21 days the core 1 is stuck at 100%. I can login to ssh but when I type in top nothing appears.

    The same thing happened to me on the previous asuswrt merlin build. When I installed the firmware I did a full factory default reset. Not sure what it is.

    Problem is solved after rebooting the router, but then after 20 days then issue appears again.
     
  7. john9527

    john9527 Part of the Furniture

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    Do you have a large ext3/4 formatted USB attached? Check the file system mount count/interval check with tune2fs.
     
    avi68 likes this.
  8. octopus

    octopus Very Senior Member

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    WAN - DDNS
    Forced refresh interval (in days) 21
    Checking every 21 days.
     
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  9. avi68

    avi68 Regular Contributor

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    Yes I have a large USB hard drive connected but I think its format is ntfs not ext.
     
  10. avi68

    avi68 Regular Contributor

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    Yes mine is set to 21 days. Is this causing the issue?

    If so how do I correct it?
     
  11. john9527

    john9527 Part of the Furniture

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    The predefined providers I'd say are pretty well debugged. Are you using a custom script? If so, I'd look there for a problem.

    @octopus - Great observation!
     
  12. sfx2000

    sfx2000 Part of the Furniture

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    Something is definitely hung up somewhere is one core is railed, and the remaining core can't respond to interactive inputs...

    I used to have a watchdog task that would check certain things, and if the dog were kicked (hung process for example) , it would do two things - grab certain log lines (like tail -n 100 /var/log/syslog) and some stack/mem data, etc - drop that into a location on flash, and then do a sysv init runlevel 6... - and this was turned on by watchdog.sh which was enable|disable (default was disable)...

    I'll have to go back and look thru the GPL, but if I recall, there is a watchdog type of task there just for things like this under the hood...
     
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  13. avi68

    avi68 Regular Contributor

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    No I'm not using any custom scripts, just the standard options from the UI
     
  14. avi68

    avi68 Regular Contributor

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    The only way I think I could test is to change the amount of refresh interval days to like 2 and see if the same problem occurs after 2 days... Just done a full reboot and everything's back to normal.
     
  15. sfx2000

    sfx2000 Part of the Furniture

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    Funny how DDNS is popping up the last couple of days - there was another thread where someone was asking to add Cloudflare as a DDNS, and RMerlin had a good response - basically due to goofiness at the DDNS provider level (API changes, etc...) - gist of the response for his build was - nano is there, and that gives folks the chance to write their own script ;)
     
  16. sfx2000

    sfx2000 Part of the Furniture

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    That would be a good first step...
     
  17. john9527

    john9527 Part of the Furniture

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    What DDNS provider?
     
  18. avi68

    avi68 Regular Contributor

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    No-ip
     
  19. avi68

    avi68 Regular Contributor

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    Ok changed the interval to 2 days. Let's see what happens........
     
  20. Andyf66

    Andyf66 Occasional Visitor

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    I've seen something very similar on my AC-87U about 3 times so far, although I'm not using DDNS. Only a hard power cycle fixes it, as a soft reset just hangs. Not sure when I first saw it though.

    One core locked at 100%. Top reports 50% idle, 50% Nice. Couldn't figure out which process was causing it though. Load average was about 5 or 6. I think it might have been tftpd, but that is a wild guess.
     
  21. avi68

    avi68 Regular Contributor

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    What does your router uptime go to before you notice this problem?

    At least you can see what processes are running, mine just doesnt respond the any commands in SSH.

    My load average also stays at about 4-5 when this problem occurs.
     
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