High CPU on A3100

[pattap]

Hi all 

I have accidently noticed that one of our A3100s, ver 5.20.99 release 5203P05, has very high CPU utilization.

There are two processes causing it, VIDL and INFO, can't find much about either of them

see the outputs below, I've attached a file as the formating of CPU history isn't the best  

dis cpu-usage history
100%|## ###### ###### ###### ###### #### ## ###### ### ## #
95%|## ###### ###### ###### ###### ####### ###### ###### #
90%|## ###### ###### ###### ###### ####### ###### ###### #
85%|## ###### ###### ###### ###### ####### ###### ###### #
80%|## ###### ###### ###### ###### ####### ###### ###### #
75%|## ###### ###### ###### ###### ####### ###### ###### #
70%|## ###### ###### ###### ###### ####### ###### ###### #
65%|## ###### ###### ###### ###### ####### ####### ###### #
60%|## ###### ###### ###### ###### ####### ####### ###### #
55%|## ###### ###### ###### ####### ####### ####### ####### #
50%|## ####### ###### ###### ####### ####### ####### ####### #
45%|## ####### ###### ####### ####### ####### ####### ####### #
40%|## ######## ############## ####### ####### ####### #########
35%|## ####################### ####### ####### ####### #########
30%|## ####################################### #################
25%|## #########################################################
20%|############################################################
15%|############################################################
10%|############################################################
5%|############################################################
------------------------------------------------------------
10 20 30 40 50 60 (minutes)

dis cpu-usage 1 verbose

===== CPU usage info (no:  0  idx: 53) =====

CPU Usage Stat. Cycle: 60 (Second)

CPU Usage            : 99%

CPU Usage Stat. Time : 2016-03-31  11:51:40

CPU Usage Stat. Tick : 0x8dde(CPU Tick High) 0xfec92cc4(CPU Tick Low)

Actual Stat. Cycle   : 0x1(CPU Tick High) 0x65a300b9(CPU Tick Low)

TaskName        CPU        Runtime(CPU Tick High/CPU Tick Low)

VIDL             1%               0/ 3c71cb3

TICK             1%               0/ 3c3cdab

STMR             0%               0/  50898b

bcmA             0%               0/  69a663

tCOU             0%               0/ 1278ba7

bcmL             8%               0/1d12af31

DQIT             0%               0/  23bcda

LPDT             0%               0/    2b26

STAT             0%               0/ 152d508

FMCK             0%               0/  3522c8

PSED             2%               0/ 77d5c18

T_DM             0%               0/  3a51b6

T_VA             0%               0/   262b8

DARP             0%               0/   5b1f2

T_ST             0%               0/   5d3c7

T_SI             0%               0/   7479f

TPBR             0%               0/  4875c3

BGRT             0%               0/  3e263c

SCAR             0%               0/  af6284

RTMC             0%               0/  74af6d

NFld             0%               0/   2a62d

FLSH             0%               0/   a0b7b

SYSM             0%               0/ 1e512ed

Rcv2             0%               0/ 16840fb

RxTk             0%               0/  646578

dANT             0%               0/    6acf

IPCB             0%               0/  7db4a5

RPCQ             0%               0/ 1208d53

  VP             0%               0/    1dbc

EXCP             0%               0/   829b1

IPCM             0%               0/   91eb5

INFO            75%               1/ d91aa4a

HAMT             0%               0/   70ccf

DEV             0%               0/  2a4d5f

SOCK             0%               0/  1a9ace

ACL             0%               0/  11f0d9

VLAN             0%               0/  8fbb9f

mac             0%               0/   839e3

LAGG             0%               0/   a5757

MSTP             4%               0/ fc18423

GARP             0%               0/  926b15

CLST             0%               0/  1d091f

NDP             0%               0/  298336

NTDP             0%               0/   a9e0d

HABP             0%               0/   bf66e

CFD             0%               0/  a88382

RRPP             0%               0/  46c493

LLDP             0%               0/ 2ef88f4

DLDP             0%               0/  2c9aa4

SMLK             0%               0/  22cd9c

MTLK             0%               0/  13dafc

ARP             0%               0/ 1e6da5f

  IP             0%               0/ 150675b

NQA             0%               0/ 13366d8

FSLH             0%               0/   7c016

FSLR             0%               0/  4ec9f8

vt0             0%               0/ 277f21f

NTPT             0%               0/  16352d

VTYD             0%               0/  4aff60

  ND             0%               0/  8ac90a

AGNT             0%               0/   89afb

TRAP             0%               0/  31876f

VMAP             0%               0/  39d8da

DT1X             0%               0/   8aef8

ACM             0%               0/  93d8df

  LS             0%               0/  2ef0da

RDS             0%               0/  29649d

  SC             0%               0/  131894

MACA             0%               0/   6e95b

NAT             0%               0/   6a19d

STND             0%               0/  1d3e52

ROUT             0%               0/ 1343b66

IFNT             0%               0/   ca895

[VoIP-Buddy]

Pattap,

The vIDL process is the idle process.  It's only using 1% of the CPU.  The INFO process, I think is the info-center.   Are you monitoring a lot of stuff?  Perhaps sending SNMP traffic to a PC?

David

[pattap]

David,

Ok good to know, I don't need to worry about idle process then. However info remains high, just checked the switch a few seconds ago and INFO porcess hits the roof. CPU history graph looks exaclty same as the one attached. 

I am monitoring a lot of stuff but do you meant that the switch itself may be sending snmp traffic?

One more thing I have noticed that one of the interface flaps, that is severla times per second, I've shut it down for now and will monitor the switch 

[pattap]

UPDATE:

After shutting the interface things settled down, I've noticed high input CRC on that interface, I suspect a faulty cable or unlikely the interface.

WIll visit the site later to confirm

[pattap]

It was just an interface that was flapping, I didn't realize this would cause such high CPU utilization