[nsp] %SCHED-3-THRASHING Question

[Ilker YILMAZ]

Hi,

 

Per two minutes I get the following logging. Has anyone come acrossed and
solved it?

 

Jun 12 19:50:05.613: %SCHED-3-THRASHING: Process thrashing on watched
message event.

-Process= "TTY Background", ipl= 4, pid= 30

-Traceback= 60493384 604935DC 603DC0D0

 

 

Cisco says:>

 

These thrashing checks are intended to determine if a process is, for some

reason, not doing its job. The thrashing check on watched queues (which is

the troublesome message which is signaling) checks the number of elements

on the queue. If this number remains the same for a given number of

schedulings, the message is printed.

 

Unfortunately, some queues are length-limited, meaning that if the router

gets very busy, the queues always stay at the maximum. As a result, the

thrashing code in the scheduler gets confused and thinks that these queues

have not been handled. The thrashing code has determined that the process

which was supposed to handle the queue was not doing its job and prints

the thrashing message.

 

The scheduler has been changed in later Cisco IOS software code. To keep

track of whether the queues have been changed (so it can better determine

whether or not the process is thrashing), the scheduler now notes whenever

an item is removed from the queue, and only prints the thrashing message

if nothing gets removed for a while.

 

Most of the time, the queue thrashing message is simply cosmetic.

 

These messages are not always caused by a software bug. They may be issued

in response to either instantaneous or sustained demand on the router.

Increased or persistent messages may indicate that the traffic load needs

to be reviewed.

 

Note: These code changes are reported under CSCdj68470. If you are a

registered user, you may use the Bug Toolkit to watch this bugID.