1LATENCYTOP(8)               System Manager's Manual              LATENCYTOP(8)
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NAME

6       latencytop - a tool for developers to visualize system latencies
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SYNOPSIS

9       latencytop [--unknown] [processes...]
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DESCRIPTION

12       This manual page documents briefly the latencytop command.
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14       latencytop  is  a  Linux* tool for software developers (both kernel and
15       userspace), aimed at identifying where in the system latency is happen‐
16       ing, and what kind of operation/action is causing the latency to happen
17       so that the code can be changed to avoid the worst latency hiccups.
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19       LatencyTOP focuses on the cases where the applications want to run  and
20       execute  useful  code,  but  there's some resource that's not currently
21       available (and the kernel then blocks the process). This is  done  both
22       on  a  system  level  and  on  a per process level, so that you can see
23       what's happening to the system, and which process is  suffering  and/or
24       causing the delays.
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26       You  can  walk  the  processes by using the cursor keys. If you press s
27       followed by a letter, then only active  processes  starting  with  that
28       lettter  are  displayed  and  walked. If you press s followed by 0 then
29       that filter is reset.
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31       If you press f then LatencyTop displays a list of  all  processes  cur‐
32       rently  waiting for an fsync to finish. Pressing f again returns you to
33       the normal operating mode of LatencyTop.
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SEE ALSO

37       powertop(1)
38       The program is more fully described at http://www.latencytop.org
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AUTHOR

41       latencytop was written by Arjan van de Ven <arjan@linux.intel.com>.
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43       This manual page was written by  Giacomo  Catenazzi  <cate@debian.org>,
44       for the Debian project (but may be used by others).
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49                               November 9, 2008                  LATENCYTOP(8)