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| About VxFS trace events | ||
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AIX trace facility lets you isolate system problems by monitoring selected system events or selected processes.
Events that can be monitored include:
Entry and exit to selected subroutines
Kernel routines
Kernel extension routines
Interrupt handlers
Trace can also be restricted to tracing a set of running processes or threads, or it can be used to initiate and trace a program.
When the trace facility is active, information is recorded in a system trace log file. The default trace log file from which the system generates a trace report is the /var/adm/ras/trcfile file. You can specify an alternate log file using the -o Name, this overrides the /var/adm/ras/trcfile default trace log file and writes trace data to a user-defined file.
See the trcrpt command that formats a report from the trace log.
You can specify your own trace log file path. Otherwise, the /var/adm/ras/trcfile is the default path.
The trace facility includes commands or subroutines for:
Activating traces - The trace command or trcstart subroutine.
Controlling traces - The trcstop command or the trcstop subroutine for stopping the tracing. While active, tracing can be suspended or resumed with the trcoff and trcon commands, or the trcoff and trcon subroutines.
Generating trace reports - The trcrpt command.
The trace report can be generated from trace event data in an already defined format. Applications and kernel extensions can use several subroutines to record additional events.
You can specify your own trace format file path. Otherwise, the /etc/trcfmt is the default path.
VxFS uses the tracing facility to trace file read-write, inode cache operation, and low memory scenario. Table: Events and trace hook identifiers shows the details of trace hooks identifier (a three- or four-digit hexadecimal number that identifies an event being traced) used for these events: