AC68U Core 1 or 2 goes 100% after a couple weeks

[john9527]

Whats the JFFS partition do anyway?

Format JFFS partition at next boot - NO
Enable JFFS custom scripts and configs - NO

Those are the settings I have. If there is no scripts/configs turned on, does that matter?

The jffs partition is used by the router to save some persistent data (sort of like nvram for other large data). It keeps your certs if you use OpenVPN or HTTPS, a copy of the syslog, data related to the clients which have connected (clientlist data), etc.

You can also customize some of the router functions with user written scripts and configs (see the wiki for more info). If you haven't written any of those, it's OK that the 'custom scripts and configs' option is No.

 

[HiVolt]

I see, thanks... I might try this on a light day here at work... maybe on a weekend.

Would having my bandwidth usage tracking to set to NVRAM - 1 per day, be an issue? But I only enabled that in April, and I've had the 100% core issue since getting the router in December, so I would think not.

 

[john9527]

I see, thanks... I might try this on a light day here at work... maybe on a weekend.

Would having my bandwidth usage tracking to set to NVRAM - 1 per day, be an issue? But I only enabled that in April, and I've had the 100% core issue since getting the router in December, so I would think not.

Hmm....speculating again. The NVRAM is a rather small space (64K). It could be that there is a bug if the NVRAM gets full and it tries to free up some NVRAM space to save the stats.

I'd recommend you change the save location to 'Custom location' and in the field to specify the location enter /jffs/ and check the radio button to 'Reset or Create data files', then hit the Apply button.

 

[Fangs404]

Just wanted to jump in here that I'm also experiencing this same issue. My top output looks similar:

Mem: 73828K used, 181880K free, 1100K shrd, 1332K buff, 7760K cached
CPU0:  0.9% usr  0.5% sys  0.0% nic 92.4% idle  0.0% io  0.0% irq  5.9% sirq
CPU1:  0.0% usr  1.3% sys  0.0% nic  0.0% idle 97.2% io  0.0% irq  1.3% sirq
Load average: 4.00 4.02 4.05 1/89 30922
  PID  PPID USER     STAT   VSZ %VSZ CPU %CPU COMMAND
  469     1 admin    R     1256  0.4   1  0.5 protect_srv
30876 30870 admin    R     1448  0.5   1  0.2 top
  491     1 admin    S     6656  2.6   0  0.1 httpd -i br0
  496     1 admin    S    10148  3.9   1  0.0 watchdog
    1     0 admin    S     6232  2.4   1  0.0 /sbin/preinit
  897     1 admin    S     6220  2.4   0  0.0 bwdpi_wred_alive
  468     1 admin    S     6220  2.4   0  0.0 /sbin/wanduck
  518     1 admin    S     6220  2.4   0  0.0 erp_monitor
  819     1 admin    S     6220  2.4   1  0.0 ntp
  842     1 admin    S     6220  2.4   0  0.0 disk_monitor
  511     1 admin    S     6220  2.4   0  0.0 hour_monitor
  747     1 admin    S     6220  2.4   1  0.0 usbled
  479     1 admin    S     6220  2.4   0  0.0 wpsaide
  500   496 admin    S     6220  2.4   0  0.0 ots
  510     1 admin    S     6220  2.4   1  0.0 bwdpi_check
  374     1 admin    S     6212  2.4   1  0.0 console
 5202  5201 admin    D     5200  2.0   0  0.0 bwdpi_sqlite -e -s NULL
  911   907 admin    S     4152  1.6   1  0.0 data_colld -i 1800 -p 43200 -b -w /tmp/bwdpi/dc/
  926   907 admin    S     4152  1.6   0  0.0 data_colld -i 1800 -p 43200 -b -w /tmp/bwdpi/dc/
  906     1 admin    S     4152  1.6   1  0.0 data_colld -i 1800 -p 43200 -b -w /tmp/bwdpi/dc/
  909   907 admin    S     4152  1.6   1  0.0 data_colld -i 1800 -p 43200 -b -w /tmp/bwdpi/dc/
  907   906 admin    S     4152  1.6   1  0.0 data_colld -i 1800 -p 43200 -b -w /tmp/bwdpi/dc/
  910   907 admin    S     4152  1.6   0  0.0 data_colld -i 1800 -p 43200 -b -w /tmp/bwdpi/dc/
  908   907 admin    S     4152  1.6   0  0.0 data_colld -i 1800 -p 43200 -b -w /tmp/bwdpi/dc/
  860   859 admin    S     2724  1.0   0  0.0 wred -B
  859   856 admin    S     2724  1.0   0  0.0 wred -B
  856     1 admin    S     2724  1.0   1  0.0 wred -B
  867   859 admin    S     2724  1.0   1  0.0 wred -B
  868   859 admin    S     2724  1.0   1  0.0 wred -B
  862   859 admin    S     2724  1.0   1  0.0 wred -B
  865   859 admin    S     2724  1.0   1  0.0 wred -B
  866   859 admin    S     2724  1.0   1  0.0 wred -B
  869   859 admin    S     2724  1.0   1  0.0 wred -B
  863   859 admin    S     2724  1.0   1  0.0 wred -B
  864   859 admin    S     2724  1.0   1  0.0 wred -B
  490     1 admin    S     2428  0.9   1  0.0 avahi-daemon: running [RT-AC68U-AC88.local]
  501     1 admin    S     2292  0.9   1  0.0 rstats
  751   748 admin    S     2200  0.8   1  0.0 u2ec
  748     1 admin    S     2200  0.8   1  0.0 u2ec
  752   751 admin    S     2200  0.8   0  0.0 u2ec
  481     1 admin    S     1752  0.6   1  0.0 nas
  508     1 admin    S     1584  0.6   0  0.0 networkmap --bootwait
16898     1 admin    S     1452  0.5   0  0.0 /sbin/udhcpc -i eth0 -p /var/run/udhcpc0.pid -s /tmp/udhcpc -O33 -O249
30870 30869 admin    S     1448  0.5   1  0.0 -sh
  376   374 admin    S     1444  0.5   1  0.0 /bin/sh
16478   496 admin    D     1444  0.5   1  0.0 cp /tmp/syslog.log /tmp/syslog.log-1 /jffs
  493     1 admin    S     1440  0.5   1  0.0 crond
  391     1 admin    S     1440  0.5   0  0.0 /sbin/klogd -c 5
 5201   511 admin    S     1440  0.5   0  0.0 sh -c bwdpi_sqlite -e -s NULL
  389     1 admin    S     1436  0.5   0  0.0 /sbin/syslogd -m 0 -S -O /tmp/syslog.log -s 256 -l 7
  485     1 nobody   S     1396  0.5   1  0.0 dnsmasq --log-async
  482     1 admin    S     1384  0.5   0  0.0 /usr/sbin/acsd
  475   469 admin    S     1256  0.4   1  0.0 protect_srv
  476   475 admin    S     1256  0.4   1  0.0 protect_srv
  749     1 admin    S     1236  0.4   1  0.0 lpd br0
  505     1 admin    S     1208  0.4   0  0.0 lld2d br0
  477     1 admin    S     1192  0.4   1  0.0 /bin/eapd
  494     1 admin    S     1164  0.4   0  0.0 /usr/sbin/infosvr br0
30869   472 admin    S     1136  0.4   0  0.0 dropbear -p 192.168.1.1:22 -s -j -k
  472     1 admin    S     1104  0.4   0  0.0 dropbear -p 192.168.1.1:22 -s -j -k
17155     1 admin    S      912  0.3   0  0.0 miniupnpd -f /etc/upnp/config
16990     1 admin    S      756  0.3   0  0.0 odhcp6c -df -R -s /tmp/dhcp6c -N try -c 000300017824af7dac88 -FP 0:dac88 -r82 -r83 eth0
  294     1 admin    S      664  0.2   1  0.0 hotplug2 --persistent --no-coldplug
  255     2 admin    SW       0  0.0   0  0.0 [mtdblock3]
    3     2 admin    SW       0  0.0   0  0.0 [ksoftirqd/0]
  385     2 admin    DWN      0  0.0   1  0.0 [jffs2_gcd_mtd4]
    7     2 admin    SW       0  0.0   1  0.0 [migration/1]
    6     2 admin    SW       0  0.0   0  0.0 [migration/0]
    9     2 admin    SW       0  0.0   1  0.0 [ksoftirqd/1]
  282     2 admin    SW       0  0.0   1  0.0 [kworker/1:1]
16759     2 admin    SW       0  0.0   0  0.0 [kworker/0:2]
   57     2 admin    DW       0  0.0   1  0.0 [sync_supers]
    5     2 admin    SW       0  0.0   1  0.0 [kworker/u:0]

I've got similar settings as the OP (HiVolt) for the JFSS partition.

A software reboot does not solve this problem. The only thing that solves it for me is to use the power button on the back of the router. Like the OP, this happens pretty regularly once the router has a moderate amount of uptime. Right now, I'm sitting at 12 days of uptime, but I'm not sure when the CPU pegged because I've been gone on travel recently.

 

[bonchien]

A software reboot does not solve this problem. The only thing that solves it for me is to use the power button on the back of the router. Like the OP, this happens pretty regularly once the router has a moderate amount of uptime. Right now, I'm sitting at 12 days of uptime, but I'm not sure when the CPU pegged because I've been gone on travel recently.

Thank you @Fangs404 for your comment. Starting yesterday I could no longer see files on my USB3 hard drive connected to my ac68u. The drive showed up in Windows 10 & 11, but no files. I tried rebooting from the user interphase multiple times, tried the USB2 port, but it was woefully slow taking over a minute to display a file directory. I finally saw your post and turned the router off using the power button then turned it on with the external drive plugged into the USB3 port. Suddenly I could see all my files on the USB3 drive again, and everything worked as it should.