Troubleshooting A Process Block - Cisco CRS-1 - Carrier Routing System Router Troubleshooting Manual

Troubleshooting High CPU Utilization and Process Timeouts

Troubleshooting a Process Block

To troubleshoot a blocked process, perform the following procedure.
SUMMARY STEPS
1.
2.
3.
DETAILED STEPS
Command or Action
Step 1
show processes blocked location node-id
Example:
RP/0/RP0/CPU0:router# show processes blocked
location 0/0/cpu0
Step 2
follow job job-id location node-id
Example:
RP/0/RP0/CPU0:router# follow job 24615 location
0/0/cpu0
Cisco IOS XR Troubleshooting Guide for the Cisco CRS-1 Router
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show processes blocked location node-id
follow job job-id location node-id
process restart job-id location node-id
Chapter 8
Purpose
Use the show processes blocked command several times
(three times at 5 second intervals) and compare the output
to determine if any processes are blocked for a long period
of time. The process can be blocked continuously or for a
few seconds. A process is blocked while it is waiting for a
response from another process.
• The Name column shows the name of the blocked
process.
The Blocked-on column shows the name and process
•
ID of the blocked process.
If the State column is Mutex, a thread in the process
•
waits for another thread. In this case, the Blocked-on
column shows the process ID and thread ID instead of
the process ID.
A blocked process can be blocked by another process.
•
If a process is being blocked by another process, you
need to track the chain of blocking and find the root of
blocking processes. Proceed to
of blocking.
Tracks the root process blocking other processes. The
follow command shows what part of the code the process is
periodically executed.
If your system is running Release 3.8.0, 3.8.1,
Caution
3.8.2, or 3.9.0 software, you should not run the
follow process and follow job commands,
because these can cause a kernel crash at the
target node. Therefore, for these software
releases, you should use other available
commands for troubleshooting and call Cisco
Technical Support if the problem is not resolved.
(This crash behavior does not occur for releases
other than the ones listed.)
Process Monitoring and Troubleshooting
Step 2 to track the chain
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