Archer C2600 Issue

Hi everyone,

From a couple of days I have a new Archer C2600 v1.1 (will replace my old C7 v2). I've noticed something curious in my C2600. The 'uptime' command is always showing some usuage:

root@C2600:~# uptime
15:43:13 up  2:11,  load average: 0.06, 0.07, 0.06

It's curious, because is working only as dumb AP (I'm testing how it goes), but, in a near future will have more functions. My old C7, was always about 0.00 in the same circumstances.

Checking with command 'top' I've found:

 1483     2 root     IW       0   0%   4% [kworker/0:1]
 1537     2 root     IW       0   0%   2% [kworker/1:2]

These processes are always consuming about 4% and 2% of CPU.

Any idea what's going on?

Tested with 2 firmwares (OpenWRT 18.06.0 RC2 / Today's snapshot found here http://ftp.halifax.rwth-aachen.de/lede/snapshots/targets/ipq806x/generic/)

Thanks a lot !!!!

kworker is a kernel worker, you will need to use dmesg to check the kernel logs.
can use echo l> /proc/sysrq-trigger for help on usage, the


# echo l> /proc/sysrq-trigger 
# dmesg | tail -1
[ 7689.648763] sysrq: SysRq : HELP : loglevel(0-9) reboot(b) crash(c) terminate-all-tasks(e) memory-full-oom-kill(f) kill-all-tasks(i) thaw-filesystems(j) show-memory-usage(m) nice-all-RT-tasks(n) poweroff(o) show-registers(p) show-all-timers(q) sync(s) show-task-states(t) unmount(u) show-blocked-tasks(w) show-tlbs(x)

Hi @mbo2o,

That's what I get:

root@C2600:~# echo 1> /proc/sysrq-trigger
root@C2600:~# dmesg | tail -1
[ 9440.227059] sysrq: SysRq : HELP : loglevel(0-9) reboot(b) crash(c) terminate-all-tasks(e) memory-full-oom-kill(f) kill-all-tasks(i) thaw-filesystems(j) show-backtrace-all-active-cpus(l) show-memory-usage(m) nice-all-RT-tasks(n) poweroff(o) show-registers(p) show-all-timers(q) sync(s) show-task-states(t) unmount(u) show-blocked-tasks(w)
root@C2600:~#

and

root@C2600:~# echo l> /proc/sysrq-trigger
root@C2600:~# dmesg | tail -1
[ 9678.502563] [<c0350060>] (cpu_startup_entry) from [<c0a00ce8>] (start_kernel+0x400/0x40c)
root@C2600:~#

Thanks,

That is the help only,
to check memory show-memory-usage(m) usage for example
use echo m> /proc/sysrq-trigger

To change the loglevel(5) use
echo 5> /proc/sysrq-trigger
then of course use dmesg to check for issues.

1 Like

Ok @mbo2o understood!!!

I'll check it!!

By the way that is very low load average from the uptime I wouldn't worry about it.

For example for me it is for all in one router

# uptime
 00:25:48 up  2:28,  load average: 0.24, 0.23, 0.19

Sorry my friend @mbo2o but I don't agree with you :grinning::grinning::grinning:

My Router 'uptime':

root@OpenWrt:~# uptime
 16:29:06 up 1 day,  7:26,  load average: 0.00, 0.00, 0.00
root@OpenWrt:~#

I've an 600 MB. symmetric fiber working on it.

Cool, everything must be done in hardware or it is very fast router to never have any process waiting for the CPU
Is that multi-core router, is your router wifi enabled as well.

I'm on an old single core cpu:

# top -b -n1
Mem: 24216K used, 35656K free, 100K shrd, 2436K buff, 7124K cached
CPU:   9% usr   9% sys   0% nic  81% idle   0% io   0% irq   0% sirq
Load average: 0.22 0.22 0.20 1/52 2284

Can you post the first three line of top for your AP

@mbo2o I've to admit I was "joking" a little. :grinning: :grinning: :grinning:

But, what I said is true, I can show you:

root@OpenWrt:/tmp# wget http://ipv4.download.thinkbroadband.com:8080/1GB.zip
--2018-07-20 16:37:16--  http://ipv4.download.thinkbroadband.com:8080/1GB.zip
Resolving ipv4.download.thinkbroadband.com... 80.249.99.148
Connecting to ipv4.download.thinkbroadband.com|80.249.99.148|:8080... connected.
HTTP request sent, awaiting response... 200 OK
Length: 1073741824 (1.0G) [application/zip]
Saving to: '1GB.zip'

1GB.zip    100%[==================== =====>]   **1.00G  62.0MB/s    in 17s**

2018-07-20 16:37:33 (61.2 MB/s) - '1GB.zip' saved [1073741824/1073741824]

root@OpenWrt:/tmp# uptime
 16:37:46 up 1 day,  7:35,  load average: 0.05, 0.01, 0.00
root@OpenWrt:/tmp#

That's my Router:

My Archer C2600 will be used as AP (replacing my old C7 v2).

Thanks @mbo2o

I Believe you but that is not a fair race you have a four core celeron.
What hardware is your AP

1 Like

That's my 'top' first lines:

Mem: 61424K used, 417984K free, 5980K shrd, 2392K buff, 15480K cached
CPU:   0% usr   5% sys   0% nic  94% idle   0% io   0% irq   0% sirq
Load average: 0.17 0.11 0.09 1/61 2376
  PID  PPID USER     STAT   VSZ %VSZ %CPU COMMAND
 2251     2 root     IW       0   0%   4% [kworker/0:1]
 1537     2 root     IW       0   0%   1% [kworker/1:2]
 2376  2365 root     R     1060   0%   0% top
 2364   783 root     S      888   0%   0% /usr/sbin/dropbear -F -P /var/run/dropbear.1.pid -p 192.168.1.230:22 -p fd2f:9e32:e071::1:22 -K 300 -T 3
  904     1 root     S     2172   0%   0% /usr/sbin/uhttpd -f -h /www -r C2600 -x /cgi-bin -u /ubus -t 60 -T 30 -k 20 -A 1 -n 3 -N 100 -R -p 0.0.0.0:80 -p [::]:80 -C /etc/uhttpd.crt -K /etc/uhttpd.key -s 0.0
 1398     1 root     S     1604   0%   0% /usr/sbin/hostapd -s -P /var/run/wifi-phy0.pid -B /var/run/hostapd-phy0.conf
 1384     1 root     S     1604   0%   0% /usr/sbin/hostapd -s -P /var/run/wifi-phy1.pid -B /var/run/hostapd-phy1.conf
  590     1 root     S     1460   0%   0% /sbin/netifd
    1     0 root     S     1340   0%   0% /sbin/procd

My AP was an Archer C7 v2, now I'm testing Archer C2600 how it goes.
One day, I'll replace my C7 for my new C2600.

Can you show the output from
# cat /proc/cpuinfo
on your AP

Here goes:

root@C2600:~# cat /proc/cpuinfo
processor       : 0
model name      : ARMv7 Processor rev 0 (v7l)
BogoMIPS        : 6.00
Features        : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32
CPU implementer : 0x51
CPU architecture: 7
CPU variant     : 0x2
CPU part        : 0x04d
CPU revision    : 0

processor       : 1
model name      : ARMv7 Processor rev 0 (v7l)
BogoMIPS        : 12.50
Features        : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32
CPU implementer : 0x51
CPU architecture: 7
CPU variant     : 0x2
CPU part        : 0x04d
CPU revision    : 0

Hardware        : Generic DT based system
Revision        : 0000
Serial          : 0000000000000000
root@C2600:~#

Out of interest I've been following this thread, and I also use a c2600 with similar values but I use it as a router.

My questions: The Load average values posted...

  • what do the 5x values listed represent?
  • are the first 3x values decimal notation for a percentage? (eg 0.17 = 17%?)

The average number of processes over a period of time that are running or ready to run(waiting or running) usually over 1min, 5min and 15minute periods.

The numbers are a count , if you are using a single CPU then you can convert to a percentage as you described. But for multiple CPUs you need to divide by the number CPU's. Not sure what the last two numbers are

https://www.tecmint.com/understand-linux-load-averages-and-monitor-performance/amp/

Hi,

Today checking 'dmesg' found that:

Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.537039] ------------[ cut here ]------------
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.537091] WARNING: CPU: 0 PID: 7 at net/core/dev.c:5586 net_rx_action+0x17c/0x31c
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.540725] Modules linked in: pppoe ppp_async ath10k_pci ath10k_core ath pppox ppp_generic nf_conntrack_ipv6 mac80211 iptable_nat ipt_REJECT ipt_MASQUERADE cfg80211 xt_time xt_tcpudp xt_state xt_nat xt_multiport xt_mark xt_mac xt_limit xt_conntrack xt_comment xt_TCPMSS xt_REDIRECT xt_LOG xt_FLOWOFFLOAD xt_CT slhc nf_reject_ipv4 nf_nat_redirect nf_nat_masquerade_ipv4 nf_conntrack_ipv4 nf_nat_ipv4 nf_nat nf_log_ipv4 nf_flow_table_hw nf_flow_table nf_defrag_ipv6 nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack iptable_mangle iptable_filter ip_tables crc_ccitt compat ledtrig_usbport ip6t_REJECT nf_reject_ipv6 nf_log_ipv6 nf_log_common ip6table_mangle ip6table_filter ip6_tables x_tables leds_gpio xhci_plat_hcd xhci_pci xhci_hcd dwc3 dwc3_of_simple ohci_platform ohci_hcd phy_qcom_dwc3 ahci ehci_platform
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.596826]  sd_mod ahci_platform libahci_platform libahci libata scsi_mod ehci_hcd gpio_button_hotplug
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.619027] CPU: 0 PID: 7 Comm: ksoftirqd/0 Not tainted 4.14.54 #0
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.628138] Hardware name: Generic DT based system
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.634423] [<c030f8e8>] (unwind_backtrace) from [<c030bb2c>] (show_stack+0x14/0x20)
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.639184] [<c030bb2c>] (show_stack) from [<c07a6ff8>] (dump_stack+0x88/0x9c)
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.647080] [<c07a6ff8>] (dump_stack) from [<c0318ecc>] (__warn+0xf0/0x11c)
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.654105] [<c0318ecc>] (__warn) from [<c0318fb8>] (warn_slowpath_null+0x20/0x28)
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.660968] [<c0318fb8>] (warn_slowpath_null) from [<c0697550>] (net_rx_action+0x17c/0x31c)
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.668606] [<c0697550>] (net_rx_action) from [<c03015c8>] (__do_softirq+0xf0/0x264)
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.676852] [<c03015c8>] (__do_softirq) from [<c031cf58>] (run_ksoftirqd+0x34/0x64)
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.684841] [<c031cf58>] (run_ksoftirqd) from [<c0339340>] (smpboot_thread_fn+0x1a8/0x1d0)
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.692220] [<c0339340>] (smpboot_thread_fn) from [<c0335738>] (kthread+0x140/0x14c)
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.700554] [<c0335738>] (kthread) from [<c0308048>] (ret_from_fork+0x14/0x2c)
Fri Jul 20 22:19:16 2018 kern.warn kernel: [31665.708523] ---[ end trace dd1c1988a8e74802 ]---

It seems something is not working fine.

OK got it @mbo2o! Thanks for that, makes much more sense now! I'm continually learning.

Looking at ...

I've found the same processes chewing up the same approximate amount of CPU time, must be normal for c2600 then (running 17.01.5 in router mode)

   20     2 root     SW       0   0%   6% [kworker/0:1]
  968     1 root     S     1596   0%   1% /usr/sbin/hostapd -s -P /var/run/wifi
 6580  5020 root     R     1052   0%   0% top

Thanks @otnert for sharing your info.

Do you have any kernel warning checking your logs files?