Chapter 9 Troubleshooting Memory; Watchdog System Monitor; Memory Monitoring - Cisco CRS-1 - Carrier Routing System Router Troubleshooting Manual

Troubleshooting Memory
Troubleshooting memory requires determining if there is a memory problem, what type of memory
problem it is, and how to resolve the problem.
This chapter contains the following sections:
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Watchdog System Monitor

Watchdog system monitor (wdsysmon) is part of the high-availability (HA) infrastructure of the
Cisco IOS XR software. Wdsysmon runs on the distributed route processor (DRP) and line cards (LCs)
with the primary goal of monitoring the system for problem conditions and attempting to recover from
them. Wdsysmon monitors the processes on each node for memory and CPU usage, deadlocks, and event
monitor conditions, as well as disk usage. If thresholds are crossed, an appropriate syslog message is
generated. The information is collected in disk0:/wdsysmon_debug. Recovery actions are taken when
memory of CPU hog or a deadlock condition is detected, whereby the process responsible for the
condition is terminated. Wdsysmon also keeps historical data on processes and posts this information to
a fault detector dynamic link library (DLL), which can then be queried by manageability applications.

Memory Monitoring

The wdsysmon memory-hog detection algorithm checks the memory state of each node in regular
intervals (every 1/10th of a second). It defines four node state thresholds:
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Processes can declare a hard memory limit in their startup file with the memory_limit keyword.
Note
OL-21483-02
Watchdog System Monitor, page 9-197
Troubleshooting Global Memory, page 9-202
Troubleshooting Process Memory, page 9-203
Normal
Minor
Severe
Critical
C H A P T E R
Cisco IOS XR Troubleshooting Guide for the Cisco CRS-1 Router
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