Changeset 7694

Timestamp:

2017-02-17T16:50:52+01:00 (8 years ago)

Author:

frrh

Message:

Protect expensive global sums of all tracers from being performed
unconditionally with a rtl (ln_ctl). This code is only relevant for
debugging or other circumstances where the user needs to know
global tracer sums for bit comarison purposes.

In normal run conditions, this calculation is redundant.

File:

• branches/UKMO/dev_r5518_MEDUSA_optim_RH/NEMOGCM/NEMO/TOP_SRC/trcstp.F90 (modified) (1 diff)

branches/UKMO/dev_r5518_MEDUSA_optim_RH/NEMOGCM/NEMO/TOP_SRC/trcstp.F90

@@ -129 +129 @@
       ENDIF
       !
-      ztrai = 0._wp                                                   !  content of all tracers
-      DO jn = 1, jptra
-         ztrai = ztrai + glob_sum( trn(:,:,:,jn) * cvol(:,:,:)   )
-      END DO
-      IF( lwp ) WRITE(numstr,9300) kt,  ztrai / areatot
-9300  FORMAT(i10,e18.10)
+      IF (ln_ctl) THEN
+         ! The following code is very expensive since it involves multiple
+         ! reproducible global sums over all tracer fields and is potentially 
+         ! called on every timestep. The results it produces are purely for
+         ! informational purposes and do not affect model evolution.
+         ! Hence we restrict its use by protecting it with the ln_ctl RTL
+         ! which should normally only be used under debugging conditions
+         ! and not in operational runs. 
+         ztrai = 0._wp                                                   !  content of all tracers
+         DO jn = 1, jptra
+            ztrai = ztrai + glob_sum( trn(:,:,:,jn) * cvol(:,:,:)   )
+         END DO
+         IF( lwp ) WRITE(numstr,9300) kt,  ztrai / areatot
+9300     FORMAT(i10,e18.10)
+      ENDIF
       !
       IF( nn_timing == 1 )   CALL timing_stop('trc_stp')