Changes between Version 241 and Version 242 of doc/app/runtime_parameters

Timestamp:

Apr 23, 2014 2:55:38 PM (11 years ago)

Author:

raasch

Comment:

--

doc/app/runtime_parameters

@@ -1285 +1285 @@
 |----------------
 {{{#!td style="vertical-align:top"
+[=#cpu_log_barrierwait '''cpu_log_barrierwait''']
+}}}
+{{{#!td style="vertical-align:top"
+L
+}}}
+{{{#!td style="vertical-align:top"
+''.F.''
+}}}
+{{{#!td
+Set an MPI-barrier at the beginning of each cpu-time measurement.\\\\
+Measurement of code performance is carried out by default for most parts of the PALM code (see routine [source:palm/trunk/SOURCE/cpulog.f90 cpu_log] for more information). In case that MPI-calls are part of code segments to be measured, the measurement might be seriously affected by idle times (if MPI-calls on some of the processors have to wait because of other, previous MPI-calls on other processors which are not yet finished). In order to avoid measuring these idle times, you can switch on an MPI-barrier at the beginning of each measurement by setting '''cpu_log_barrierwait''' = ''.TRUE.''. You should keep in mind that these additional barriers may generally degrade the code performance, so they should be switched on only for getting precise cpu-time measurements (and not for production runs).
+}}}
+|----------------
+{{{#!td style="vertical-align:top"
 [=#npex '''npex''']
 }}}