.TH LATENCYTOP 8 "November 9, 2008"
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.SH NAME
latencytop \- a tool for developers to visualize system latencies
.SH SYNOPSIS
.B latencytop
.RI [ --unknown ] " " [ processes ... ]
.SH DESCRIPTION
This manual page documents briefly the
.B latencytop
command.
.PP
.\" TeX users may be more comfortable with the \fB<whatever>\fP and
.\" \fI<whatever>\fP escape sequences to invode bold face and italics, 
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\fBlatencytop\fP is a Linux* tool for software developers (both kernel
and userspace), aimed at identifying where in the system latency is
happening, and what kind of operation/action is causing the latency to
happen so that the code can be changed to avoid the worst latency
hiccups.
.PP
\fBLatencyTOP\fP focuses on the cases where the applications want to
run and execute useful code, but there's some resource that's not
currently available (and the kernel then blocks the process). This is
done both on a system level and on a per process level, so that you can
see what's happening to the system, and which process is suffering
and/or causing the delays. 

You can walk the processes by using the cursor keys. If you press \fBs\fP 
followed by a letter, then only active processes starting with that lettter
are displayed and walked. If you press \fBs\fP followed by \fB0\fP then
that filter is reset.

If you press \fBf\fP then \fBLatencyTop\fP displays a list of all processes
currently waiting for an \fBfsync\fP to finish. Pressing \fBf\fP again
returns you to the normal operating mode of \fBLatencyTop\fP.

.SH SEE ALSO
.BR powertop (1)
.br
The program is more fully described at http://www.latencytop.org
.SH AUTHOR
latencytop was written by Arjan van de Ven <arjan@linux.intel.com>.
.PP
This manual page was written by Giacomo Catenazzi <cate@debian.org>,
for the Debian project (but may be used by others).