doc: update about statistics

doc/chapters/configuration.texi

@@ -210,7 +210,7 @@ Enable performance model debugging.
 
 @defvr {Configure option} --enable-stats
 @c see ../../src/datawizard/datastats.c
-Enable gathering of various data statistics.
+Enable gathering of various data statistics (@pxref{Data statistics}).
 @end defvr
 
 @defvr {Configure option} --enable-maxbuffers
@@ -547,11 +547,13 @@ Display memory statistics on data which have not been unregistered at the end of
 @end defvr
 
 @defvr {Environment variable} STARPU_BUS_STATS
-When defined, statistics about the bus will be displayed when calling
-@code{starpu_shutdown()} (@pxref{Execution statistics}).
+When defined, statistics about data transfers will be displayed when calling
+@code{starpu_shutdown()} (@pxref{Profiling}).
 @end defvr
 
 @defvr {Environment variable} STARPU_WORKER_STATS
 When defined, statistics about the workers will be displayed when calling
-@code{starpu_shutdown()} (@pxref{Execution statistics}).
+@code{starpu_shutdown()} (@pxref{Profiling}). When combined with the
+environment variable @code{STARPU_PROFILING}, it displays the power
+consumption (@pxref{Power-based scheduling}).
 @end defvr

doc/chapters/perf-feedback.texi

@@ -12,7 +12,7 @@
 * Codelet performance::         Performance of codelets
 * Theoretical lower bound on execution time API::  
 * Memory feedback::             
-* Execution statistics::        
+* Data statistics::        
 @end menu
 
 @node On-line
@@ -495,13 +495,21 @@ Node #3
 	Invalidated (was Owner) : 0
 @end example
 
-@node Execution statistics
-@section Execution statistics
+@node Data statistics
+@section Data statistics
+
+Different data statistics can be displayed at the end of the execution
+of the application. To enable them, you need to pass the option
+@code{--enable-stats} when calling @code{configure}. When calling
+@code{starpu_shutdown()} various statistics will be displayed,
+execution, MSI cache statistics, allocation cache statistics, and data
+transfer statistics.
+
+@c TODO: data transfer stats are similar to the ones displayed when
+@c setting STARPU_BUS_STATS
+
+
+
 
-Different statistics can be displayed at the end of the execution of
-the application. To enable them, you need to pass the option
-@code{--enable-stats} when calling @code{configure} and/or set
-the environment variables @code{STARPU_BUS_STATS} and
-@code{STARPU_WORKER_STATS} when calling your application.