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The supremim integral power of 2 of the load seen thus far

=item cpu

CPU idle time (multiplied by 1000)

=item ncpu

Number of CPU

=item tmem

Total memory in bytes

=item amem

Available memory in bytes

=item numbacked

Number of requests backhanded

=item tatime

Averages time (in milliseconds) to serve a backhanded request

=back

This structure sounds worse than it is.  It's really quite simple to use:

  foreach my $server ($serverstats) {
      print $server->{'mtime'}, "\n";
      $server->{'load'} += 1;
  }

Note that each of the elements of the hashes is magically tied directly (for
both reads and writes) into the shared memory segment where serverstats
resides.  You can call load_serverstats() once, and use the returned structure
as much as you want - it will always reflect the contents of the underlying
shared structure.  This has one drawback, however, which is that you cannot
call load_serverstats() until after the shared memory segment has been created
and attached.  I recommend a PerlChildInit handler to do load_serverstats()
into a global variable.

=item B<load_personal_arriba>

This function returns a reference to a scalar variable which is magically
tied to the global mod_backhand_personal_arriba integer.  This contains the
arriba speed of the local machine.

=back

=head1 CAVEATS

As explained above, you cannot PerlModule or use() or require()
Apache::Backhand until *after* mod_backhand (and mod_perl, of course) are
linked into the server.

As explained above, you cannot call load_serverstats() until *after* the
shared memory segment has been created and attached.  The best place to do
this is the child init phase.

It's easy to make mod_backhand coredump by doing Bad Things to serverstats
(e.g. 'foreach (@{$serverstats}) { $_->{'mtime'} = time() }'...)
Even though I've provided the magic to make serverstats writeable, this should
be treated with care.

There is necessarily going to be a small amount of overhead when calling perl
candidacy functions.  I highly recommend calling byAge *before* calling any
perl candidacy functions, because converting the server list into a perl array
and back again is one of the most expensive operations byPerl has to perform,
and byAge tends to knock out a lot of unnecessary work.

=head1 BUGS

Hopefully none.

=head1 AUTHOR

J. David Lowe, dlowe@pootpoot.com

=head1 SEE ALSO

perl(1)

=cut