+ * Get the initial time of the request, based either on $wgRequestTime or
+ * $wgRUstart. Will return null if not able to find data.
+ *
+ * @param string|bool $metric Metric to use, with the following possibilities:
+ * - user: User CPU time (without system calls)
+ * - cpu: Total CPU time (user and system calls)
+ * - wall (or any other string): elapsed time
+ * - false (default): will fall back to default metric
+ * @return float|null
+ */
+ protected function getTime( $metric = 'wall' ) {
+ if ( $metric === 'cpu' || $metric === 'user' ) {
+ $ru = wfGetRusage();
+ if ( !$ru ) {
+ return 0;
+ }
+ $time = $ru['ru_utime.tv_sec'] + $ru['ru_utime.tv_usec'] / 1e6;
+ if ( $metric === 'cpu' ) {
+ # This is the time of system calls, added to the user time
+ # it gives the total CPU time
+ $time += $ru['ru_stime.tv_sec'] + $ru['ru_stime.tv_usec'] / 1e6;
+ }
+ return $time;
+ } else {
+ return microtime( true );
+ }
+ }
+
+ /**
+ * Get the initial time of the request, based either on $wgRequestTime or
+ * $wgRUstart. Will return null if not able to find data.
+ *
+ * @param string|bool $metric Metric to use, with the following possibilities:
+ * - user: User CPU time (without system calls)
+ * - cpu: Total CPU time (user and system calls)
+ * - wall (or any other string): elapsed time
+ * - false (default): will fall back to default metric
+ * @return float|null