Troubleshooting High Cpu Utilization And Process Timeouts; General Guidelines For Troubleshooting Cpu Utilization Problems - Cisco CRS-1 - Carrier Routing System Router Troubleshooting Manual

Chapter 8 Process Monitoring and Troubleshooting
If the hog is persistent and the node is reset, contact Cisco Technical Support. For contact information
for Cisco Technical Support, see the
section on page viii
system log and provide the representative with the gathered information.
For more information on wdsysmon and memory thresholds, see the
Note
section on page 9-197

Troubleshooting High CPU Utilization and Process Timeouts

This section describes the troubleshooting of common problems that can occur due to high CPU
utilization, and in some cases causing process timeouts. It includes the following topics:
•
•
•
•
•
•
•

General Guidelines for Troubleshooting CPU Utilization Problems

Optimal CPU utilization is vital for the routers to function properly. In general, the following cases can
cause high CPU utilization:
•
•
There is no single definition of "high CPU utilization." Utilization depends on many factors, including
the number of clients served and the current configuration on the router. The following example
illustrates one approach to troubleshooting utilization. (Details of the commands are provided in the
sections that follow.)
Example:
OL-21483-02
in the Preface. Copy the error message exactly as it appears on the console or in the
in Chapter 9, "Troubleshooting Memory."
General Guidelines for Troubleshooting CPU Utilization Problems, page 8-185
Troubleshooting a Process Block, page 8-188
Troubleshooting a Process Crash on Line Cards, page 8-192
Troubleshooting a Memory Leak, page 8-193
Troubleshooting a Hardware Failure, page 8-194
Troubleshooting SNMP Timeouts, page 8-194
Troubleshooting Communication Among Multiple Processes, page 8-194
Normal conditions—One or more processes might be using a large percentage (or all) of the
available CPU due to the following reasons:
Routing table convergence calculations (until the routing table converges)
–
SNMP polling
–
– Any query that requires a large amount of CPU
– Communication among multiple processes
Abnormal conditions—A process might be using excessive CPU due to the following reasons:
Process (thread) loop
–
Memory leak
–
Process blocking due to bug or hardware problem that causes other process(es) waiting for a
–
reply (loop)
You run the top processes command. (It shows the top ten processes in terms of CPU usage.)
Troubleshooting High CPU Utilization and Process Timeouts
"Obtaining Documentation and Submitting a Service Request"
Cisco IOS XR Troubleshooting Guide for the Cisco CRS-1 Router
"Watchdog System Monitor"
8-185