CPU usage rate is too high.

patrick.zhang · ‎09-03-2002

I have a cisco2509 router with a NM-8A/S,use reverse telnet to connect other 3 cisco2610 console through cisco2509 As-port.I found often the CPU usage rate is too high,and the line 1,2,3 often being connecting with a asterisk automaticlly.I don't know why.Follows is the result of show-proc-cpu/show-line commands.

c2509#sh proc cpu

CPU utilization for five seconds: 86%/1%; one minute: 88%; five minutes: 89%

PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process

1 47936 85676 559 0.00% 0.01% 0.00% 0 Load Meter

2 144464 82529 1750 0.08% 0.19% 0.19% 0 IP-EIGRP Hello

3 1204508 79663 15120 0.00% 0.20% 0.23% 0 Check heaps

4 0 1 0 0.00% 0.00% 0.00% 0 Chunk Manager

5 0 1 0 0.00% 0.00% 0.00% 0 Pool Manager

6 4 2 2000 0.00% 0.00% 0.00% 0 Timers

7 48 5 9600 0.00% 0.00% 0.00% 0 Serial Backgroun

8 22584 21466 1052 0.00% 0.02% 0.00% 0 ARP Input

9 4 4 1000 0.00% 0.00% 0.00% 0 DDR Timers

10 4 2 2000 0.00% 0.00% 0.00% 0 Dialer event

11 16 2 8000 0.00% 0.00% 0.00% 0 Entity MIB API

12 0 1 0 0.00% 0.00% 0.00% 0 SERIAL A'detect

13 0 1 0 0.00% 0.00% 0.00% 0 Critical Bkgnd

14 110184 64667 1703 0.16% 0.05% 0.02% 0 Net Background

15 80 185 432 0.00% 0.00% 0.00% 0 Logger

16 70776 427761 165 0.08% 0.08% 0.07% 0 TTY Background

17 48552 427790 113 0.00% 0.03% 0.02% 0 Per-Second Jobs

18 43500 88035 494 0.00% 0.00% 0.00% 0 Net Input

19 44512 85677 519 0.00% 0.05% 0.05% 0 Compute load avg

20 292260 7142 40921 0.88% 0.10% 0.06% 0 Per-minute Jobs

21 193884 172505 1123 0.00% 0.21% 0.13% 0 IP Input

PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process

22 78212 57151 1368 0.16% 0.02% 0.00% 0 CDP Protocol

23 0 1 0 0.00% 0.00% 0.00% 0 X.25 Encaps Mana

24 0 1 0 0.00% 0.00% 0.00% 0 Asy FS Helper

25 0 1 0 0.00% 0.00% 0.00% 0 PPP IP Add Route

26 184384 7182 25673 0.48% 0.05% 0.00% 0 IP Background

27 53216 7148 7444 0.16% 0.01% 0.00% 0 Adj Manager

28 6244 5561 1122 0.00% 0.03% 0.00% 0 TCP Timer

29 236 45 5244 0.00% 0.00% 0.00% 0 TCP Protocols

30 0 1 0 0.00% 0.00% 0.00% 0 Probe Input

31 0 1 0 0.00% 0.00% 0.00% 0 RARP Input

32 0 1 0 0.00% 0.00% 0.00% 0 HTTP Timer

33 0 1 0 0.00% 0.00% 0.00% 0 Socket Timers

34 6372 1775 3589 0.00% 0.01% 0.00% 0 DHCPD Receive

35 1868 7141 261 0.00% 0.00% 0.00% 0 IP Cache Ager

36 0 1 0 0.00% 0.00% 0.00% 0 PAD InCall

37 4 2 2000 0.00% 0.00% 0.00% 0 X.25 Background

38 49696 12979 3828 3.00% 0.39% 0.08% 0 Exec

39 540 172 3139 0.00% 0.09% 0.02% 3 TTY Daemon

40 48032 41804 1148 0.00% 0.05% 0.06% 0 IP-EIGRP Router

41 784 3573 219 0.00% 0.00% 0.00% 0 DHCPD Timer

42 37860 121331 312 0.00% 0.00% 0.00% 0 DHCPD Database

43 14792 4851 3049 0.00% 0.00% 0.00% 1 TTY Daemon

PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process

44 5154476 838477 6147 82.93% 86.61% 87.64% 2 Exec

c2509#c2509#sh proc cpu

CPU utilization for five seconds: 86%/1%; one minute: 88%; five minutes: 89%

PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process

1 47936 85676 559 0.00% 0.01% 0.00% 0 Load Meter

2 144464 82529 1750 0.08% 0.19% 0.19% 0 IP-EIGRP Hello

3 1204508 79663 15120 0.00% 0.20% 0.23% 0 Check heaps

4 0 1 0 0.00% 0.00% 0.00% 0 Chunk Manager

5 0 1 0 0.00% 0.00% 0.00% 0 Pool Manager

6 4 2 2000 0.00% 0.00% 0.00% 0 Timers

7 48 5 9600 0.00% 0.00% 0.00% 0 Serial Backgroun

8 22584 21466 1052 0.00% 0.02% 0.00% 0 ARP Input

9 4 4 1000 0.00% 0.00% 0.00% 0 DDR Timers

10 4 2 2000 0.00% 0.00% 0.00% 0 Dialer event

11 16 2 8000 0.00% 0.00% 0.00% 0 Entity MIB API

12 0 1 0 0.00% 0.00% 0.00% 0 SERIAL A'detect

13 0 1 0 0.00% 0.00% 0.00% 0 Critical Bkgnd

14 110184 64667 1703 0.16% 0.05% 0.02% 0 Net Background

15 80 185 432 0.00% 0.00% 0.00% 0 Logger

16 70776 427761 165 0.08% 0.08% 0.07% 0 TTY Background

17 48552 427790 113 0.00% 0.03% 0.02% 0 Per-Second Jobs

18 43500 88035 494 0.00% 0.00% 0.00% 0 Net Input

19 44512 85677 519 0.00% 0.05% 0.05% 0 Compute load avg

20 292260 7142 40921 0.88% 0.10% 0.06% 0 Per-minute Jobs

21 193884 172505 1123 0.00% 0.21% 0.13% 0 IP Input

PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process

22 78212 57151 1368 0.16% 0.02% 0.00% 0 CDP Protocol

23 0 1 0 0.00% 0.00% 0.00% 0 X.25 Encaps Mana

24 0 1 0 0.00% 0.00% 0.00% 0 Asy FS Helper

25 0 1 0 0.00% 0.00% 0.00% 0 PPP IP Add Route

26 184384 7182 25673 0.48% 0.05% 0.00% 0 IP Background

27 53216 7148 7444 0.16% 0.01% 0.00% 0 Adj Manager

28 6244 5561 1122 0.00% 0.03% 0.00% 0 TCP Timer

29 236 45 5244 0.00% 0.00% 0.00% 0 TCP Protocols

30 0 1 0 0.00% 0.00% 0.00% 0 Probe Input

31 0 1 0 0.00% 0.00% 0.00% 0 RARP Input

32 0 1 0 0.00% 0.00% 0.00% 0 HTTP Timer

33 0 1 0 0.00% 0.00% 0.00% 0 Socket Timers

34 6372 1775 3589 0.00% 0.01% 0.00% 0 DHCPD Receive

35 1868 7141 261 0.00% 0.00% 0.00% 0 IP Cache Ager

36 0 1 0 0.00% 0.00% 0.00% 0 PAD InCall

37 4 2 2000 0.00% 0.00% 0.00% 0 X.25 Background

38 49696 12979 3828 3.00% 0.39% 0.08% 0 Exec

39 540 172 3139 0.00% 0.09% 0.02% 3 TTY Daemon

40 48032 41804 1148 0.00% 0.05% 0.06% 0 IP-EIGRP Router

41 784 3573 219 0.00% 0.00% 0.00% 0 DHCPD Timer

42 37860 121331 312 0.00% 0.00% 0.00% 0 DHCPD Database

43 14792 4851 3049 0.00% 0.00% 0.00% 1 TTY Daemon

PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process

44 5154476 838477 6147 82.93% 86.61% 87.64% 2 Exec

c2509#

steve.barlow · ‎09-04-2002

The virtual EXEC process handles virtual type terminal (vty) lines, such as Telnet sessions on the router. If you've issued a command that generates long output (such as show tech-support), or if the debug output has been redirected to the vty (using the terminal monitor or the no logging console command), the amount of CPU resources used by the virtual EXEC process increases.

Hope that helps

DALE FRANCIS · ‎09-04-2002

Hi,

As been pointed out, it's the EXEC process contributing all the load, it is not uncommon to see very high CPU loads during commands such as sh tech or sh mem proc etc.

Howeve it should not remain hi for 3 -4 min, if you see that it does then issue the following command

sh proc cp | exc 0.00%

This will show which PID is taking all the CPU timeslots.

Also you might want to try the command service nagle, this command is used to bunch your telnet characters and responses into a larger packet and then out that packet out onto the wire at the rate equal to the RTT (Round Trip Timer) for that particular connection.

There are some caveats when this can cause trouble tho, DLSW, XREMOTE etc might be affected by this command.

Regards