lockbydist.d.1m   [plain text]


.TH lockbydist.d 1m  "May 16, 2005" "version 1.00" "USER COMMANDS"
.SH NAME
lockbydist.d \- lock distrib. by process name. Uses DTrace.
.SH SYNOPSIS
.B lockbydist.d
.SH DESCRIPTION
lockbydist.d is a DTrace OneLiner to a report the time threads have
spent blocked on adaptive mutexes, by process name. 

A distribution is printed to illustrate the number of blocks at 
different lengths in time. This helps us identify if there are many
short blocks, or fewer large blocks.

Docs/oneliners.txt and Docs/Examples/oneliners_examples.txt
in the DTraceToolkit contain this as a oneliner that can be cut-n-paste
to run.

Since this uses DTrace, only the root user or users with the
dtrace_kernel privilege can run this command.
.SH EXAMPLES
.TP
This samples until Ctrl\-C is hit.
# 
.B lockbydist.d
.PP
.SH FIELDS
.TP
process name
The process name. There may be several PIDs that have the 
same process name, for example with numerous instances of "bash". The
value reported will be the sum of them all.
.TP
value
The blocked time in nanoseconds
.TP
count
The number of occurrences that were at least this size 
.PP
.SH DOCUMENTATION
See the DTraceToolkit for further documentation under the 
Docs directory. The DTraceToolkit docs may include full worked
examples with verbose descriptions explaining the output.
.SH EXIT
lockbydist.d will sample until Ctrl\-C is hit.
.SH AUTHOR
Brendan Gregg
[Sydney, Australia]
.SH SEE ALSO
lockstat(1M), dtrace(1M)