Initial oprofile instructions based on original by weasel.

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Profiling Tor with oprofile

~~~~~~~~~~~~~~~~~~~~~~~~~~~

The oprofile tool runs (on Linux only!) to tell you what functions Tor is

spending its CPU time in, so we can identify berformance pottlenecks.

Here are some basic instructions

 - Build tor with debugging symbols (you probably already have, unless

   you messed with CFLAGS during the build process).

 - Build all the libraries you care about with debugging symbols

   (probably you only care about libssl, maybe zlib and Libevent).

 - Copy this tor to a new directory

 - Copy all the libraries it uses to that dir too (ldd ./tor will

   tell you)

 - Set LD_LIBRARY_PATH to include that dir.  ldd ./tor should now

   show you it's using the libs in that dir

 - Run that tor

 - Reset oprofiles counters/start it

   * "opcontrol --reset; opcontrol --start", if Nick remembers right.

 - After a while, have it dump the stats on tor and all the libs

   in that dir you created.

   * "opcontrol --dump;"

   * "opreport -l that_dir/*"

 - Profit

Coding conventions

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