Index: NEMO/branches/2018/dev_r9759_HPC09_ESIWACE/tests/BENCH/EXPREF/namelist_cfg_orca025_like
===================================================================
--- NEMO/branches/2018/dev_r9759_HPC09_ESIWACE/tests/BENCH/EXPREF/namelist_cfg_orca025_like	(revision 9766)
+++ NEMO/branches/2018/dev_r9759_HPC09_ESIWACE/tests/BENCH/EXPREF/namelist_cfg_orca025_like	(revision 9772)
@@ -26,4 +26,6 @@
    jpni        =   3       !  jpni   number of processors following i (set automatically if < 1)
    jpnj        =   3       !  jpnj   number of processors following j (set automatically if < 1)
+   nn_comm_mod  =   1      !  step routine call frequency
+   ln_comm_only = .false.  !  replace step routine by realistic communications only
 /
 !-----------------------------------------------------------------------
Index: NEMO/branches/2018/dev_r9759_HPC09_ESIWACE/tests/BENCH/EXPREF/namelist_cfg_orca12_like
===================================================================
--- NEMO/branches/2018/dev_r9759_HPC09_ESIWACE/tests/BENCH/EXPREF/namelist_cfg_orca12_like	(revision 9766)
+++ NEMO/branches/2018/dev_r9759_HPC09_ESIWACE/tests/BENCH/EXPREF/namelist_cfg_orca12_like	(revision 9772)
@@ -26,4 +26,6 @@
    jpni        =   3       !  jpni   number of processors following i (set automatically if < 1)
    jpnj        =   3       !  jpnj   number of processors following j (set automatically if < 1)
+   nn_comm_mod  =   1      !  step routine call frequency
+   ln_comm_only = .false.  !  replace step routine by realistic communications only
 /
 !-----------------------------------------------------------------------
Index: NEMO/branches/2018/dev_r9759_HPC09_ESIWACE/tests/BENCH/EXPREF/namelist_cfg_orca1_like
===================================================================
--- NEMO/branches/2018/dev_r9759_HPC09_ESIWACE/tests/BENCH/EXPREF/namelist_cfg_orca1_like	(revision 9766)
+++ NEMO/branches/2018/dev_r9759_HPC09_ESIWACE/tests/BENCH/EXPREF/namelist_cfg_orca1_like	(revision 9772)
@@ -26,4 +26,6 @@
    jpni        =   3       !  jpni   number of processors following i (set automatically if < 1)
    jpnj        =   3       !  jpnj   number of processors following j (set automatically if < 1)
+   nn_comm_mod  =   1      !  step routine call frequency
+   ln_comm_only = .false.  !  replace step routine by realistic communications only
 /
 !-----------------------------------------------------------------------
Index: NEMO/branches/2018/dev_r9759_HPC09_ESIWACE/tests/BENCH/MY_SRC/restart.F90
===================================================================
--- NEMO/branches/2018/dev_r9759_HPC09_ESIWACE/tests/BENCH/MY_SRC/restart.F90	(revision 9772)
+++ NEMO/branches/2018/dev_r9759_HPC09_ESIWACE/tests/BENCH/MY_SRC/restart.F90	(revision 9772)
@@ -0,0 +1,316 @@
+MODULE restart
+   !!======================================================================
+   !!                     ***  MODULE  restart  ***
+   !! Ocean restart :  write the ocean restart file
+   !!======================================================================
+   !! History :  OPA  !  1999-11  (M. Imbard)  Original code
+   !!   NEMO     1.0  !  2002-08  (G. Madec)  F90: Free form
+   !!            2.0  !  2006-07  (S. Masson)  use IOM for restart
+   !!            3.3  !  2010-04  (M. Leclair, G. Madec)  modified LF-RA
+   !!            - -  !  2010-10  (C. Ethe, G. Madec) TRC-TRA merge (T-S in 4D)
+   !!            3.7  !  2014-01  (G. Madec) suppression of curl and hdiv from the restart
+   !!             -   !  2014-12  (G. Madec) remove KPP scheme
+   !!----------------------------------------------------------------------
+
+   !!----------------------------------------------------------------------
+   !!   rst_opn    : open the ocean restart file
+   !!   rst_write  : write the ocean restart file
+   !!   rst_read   : read the ocean restart file
+   !!----------------------------------------------------------------------
+   USE oce             ! ocean dynamics and tracers 
+   USE dom_oce         ! ocean space and time domain
+   USE sbc_ice         ! only lk_si3 
+   USE phycst          ! physical constants
+   USE eosbn2          ! equation of state            (eos bn2 routine)
+   USE trdmxl_oce      ! ocean active mixed layer tracers trends variables
+   !
+   USE in_out_manager  ! I/O manager
+   USE iom             ! I/O module
+   USE diurnal_bulk
+
+   IMPLICIT NONE
+   PRIVATE
+
+   PUBLIC   rst_opn         ! routine called by step module
+   PUBLIC   rst_write       ! routine called by step module
+   PUBLIC   rst_read        ! routine called by istate module
+   PUBLIC   rst_read_open   ! routine called in rst_read and (possibly) in dom_vvl_init
+
+   !! * Substitutions
+#  include "vectopt_loop_substitute.h90"
+   !!----------------------------------------------------------------------
+   !! NEMO/OCE 4.0 , NEMO Consortium (2018)
+   !! $Id: restart.F90 9654 2018-05-28 09:08:53Z clem $
+   !! Software governed by the CeCILL licence     (./LICENSE)
+   !!----------------------------------------------------------------------
+CONTAINS
+
+   SUBROUTINE rst_opn( kt )
+      !!---------------------------------------------------------------------
+      !!                   ***  ROUTINE rst_opn  ***
+      !!                     
+      !! ** Purpose : + initialization (should be read in the namelist) of nitrst 
+      !!              + open the restart when we are one time step before nitrst
+      !!                   - restart header is defined when kt = nitrst-1
+      !!                   - restart data  are written when kt = nitrst
+      !!              + define lrst_oce to .TRUE. when we need to define or write the restart
+      !!----------------------------------------------------------------------
+      INTEGER, INTENT(in) ::   kt     ! ocean time-step
+      !!
+      CHARACTER(LEN=20)   ::   clkt     ! ocean time-step deine as a character
+      CHARACTER(LEN=50)   ::   clname   ! ocean output restart file name
+      CHARACTER(lc)       ::   clpath   ! full path to ocean output restart file
+      CHARACTER(LEN=52)   ::   clpname   ! ocean output restart file name including prefix for AGRIF
+      CHARACTER(LEN=256)  ::   clinfo    ! info character
+      !!----------------------------------------------------------------------
+      !
+      IF( kt == nit000 ) THEN   ! default definitions
+         lrst_oce = .FALSE.   
+         IF( ln_rst_list ) THEN
+            nrst_lst = 1
+            nitrst = nstocklist( nrst_lst )
+         ELSE
+            nitrst = nitend
+         ENDIF
+      ENDIF
+
+      ! frequency-based restart dumping (nn_stock)
+      IF( .NOT. ln_rst_list .AND. MOD( kt - 1, nstock ) == 0 ) THEN   
+         ! we use kt - 1 and not kt - nit000 to keep the same periodicity from the beginning of the experiment
+         nitrst = kt + nstock - 1                  ! define the next value of nitrst for restart writing
+         IF( nitrst > nitend )   nitrst = nitend   ! make sure we write a restart at the end of the run
+      ENDIF
+      ! to get better performances with NetCDF format:
+      ! we open and define the ocean restart file one time step before writing the data (-> at nitrst - 1)
+      ! except if we write ocean restart files every time step or if an ocean restart file was writen at nitend - 1
+      IF( kt == nitrst - 1 .OR. nstock == 1 .OR. ( kt == nitend .AND. .NOT. lrst_oce ) ) THEN
+         IF( nitrst <= nitend .AND. nitrst > 0 ) THEN 
+            ! beware of the format used to write kt (default is i8.8, that should be large enough...)
+            IF( nitrst > 999999999 ) THEN   ;   WRITE(clkt, *       ) nitrst
+            ELSE                            ;   WRITE(clkt, '(i8.8)') nitrst
+            ENDIF
+            ! create the file
+            clname = TRIM(cexper)//"_"//TRIM(ADJUSTL(clkt))//"_"//TRIM(cn_ocerst_out)
+            clpath = TRIM(cn_ocerst_outdir)
+            IF( clpath(LEN_TRIM(clpath):) /= '/' ) clpath = TRIM(clpath) // '/'
+            IF(lwp) THEN
+               WRITE(numout,*)
+               IF(.NOT.lwxios) THEN
+                  SELECT CASE ( jprstlib )
+                  CASE DEFAULT         ;   WRITE(numout,*)                            &
+                      '             open ocean restart NetCDF file: ',TRIM(clpath)//TRIM(clname)
+                  END SELECT
+                  IF ( snc4set%luse )      WRITE(numout,*) '             opened for NetCDF4 chunking and compression'
+                  IF( kt == nitrst - 1 ) THEN   ;   WRITE(numout,*) '             kt = nitrst - 1 = ', kt
+                  ELSE                          ;   WRITE(numout,*) '             kt = '             , kt
+                  ENDIF
+               ENDIF
+            ENDIF
+            !
+            IF(.NOT.lwxios) THEN
+               !EM no call to restart opening
+               !EM CALL iom_open( TRIM(clpath)//TRIM(clname), numrow, ldwrt = .TRUE., kiolib = jprstlib )
+            ELSE
+#if defined key_iomput
+               cwxios_context = "rstw_"//TRIM(ADJUSTL(clkt))
+               IF( TRIM(Agrif_CFixed()) == '0' ) THEN
+                  clpname = clname
+               ELSE
+                  clpname = TRIM(Agrif_CFixed())//"_"//clname   
+               ENDIF
+               CALL iom_init( cwxios_context, TRIM(clpath)//TRIM(clpname))
+               CALL xios_update_calendar(nitrst)
+               CALL iom_swap(      cxios_context          )
+#else
+               clinfo = 'Can not use XIOS in rst_opn'
+               CALL ctl_stop(TRIM(clinfo))
+#endif
+            ENDIF
+               !EM restart writing
+            !EM lrst_oce = .TRUE.
+         ENDIF
+      ENDIF
+      !
+   END SUBROUTINE rst_opn
+
+
+   SUBROUTINE rst_write( kt )
+      !!---------------------------------------------------------------------
+      !!                   ***  ROUTINE rstwrite  ***
+      !!                     
+      !! ** Purpose :   Write restart fields in the format corresponding to jprstlib
+      !!
+      !! ** Method  :   Write in numrow when kt == nitrst in NetCDF
+      !!              file, save fields which are necessary for restart
+      !!----------------------------------------------------------------------
+      INTEGER, INTENT(in) ::   kt   ! ocean time-step
+      !!----------------------------------------------------------------------
+                     IF(lwxios) CALL iom_swap(      cwxios_context          )
+                     CALL iom_rstput( kt, nitrst, numrow, 'rdt'    , rdt       , ldxios = lwxios)   ! dynamics time step
+
+      IF ( .NOT. ln_diurnal_only ) THEN
+                     CALL iom_rstput( kt, nitrst, numrow, 'ub'     , ub, ldxios = lwxios        )     ! before fields
+                     CALL iom_rstput( kt, nitrst, numrow, 'vb'     , vb, ldxios = lwxios        )
+                     CALL iom_rstput( kt, nitrst, numrow, 'tb'     , tsb(:,:,:,jp_tem), ldxios = lwxios )
+                     CALL iom_rstput( kt, nitrst, numrow, 'sb'     , tsb(:,:,:,jp_sal), ldxios = lwxios )
+                     CALL iom_rstput( kt, nitrst, numrow, 'sshb'   , sshb, ldxios = lwxios      )
+                     !
+                     CALL iom_rstput( kt, nitrst, numrow, 'un'     , un, ldxios = lwxios        )     ! now fields
+                     CALL iom_rstput( kt, nitrst, numrow, 'vn'     , vn, ldxios = lwxios        )
+                     CALL iom_rstput( kt, nitrst, numrow, 'tn'     , tsn(:,:,:,jp_tem), ldxios = lwxios )
+                     CALL iom_rstput( kt, nitrst, numrow, 'sn'     , tsn(:,:,:,jp_sal), ldxios = lwxios )
+                     CALL iom_rstput( kt, nitrst, numrow, 'sshn'   , sshn, ldxios = lwxios      )
+                     CALL iom_rstput( kt, nitrst, numrow, 'rhop'   , rhop, ldxios = lwxios      )
+                  ! extra variable needed for the ice sheet coupling
+                  IF ( ln_iscpl ) THEN 
+                     CALL iom_rstput( kt, nitrst, numrow, 'tmask'  , tmask, ldxios = lwxios ) ! need to extrapolate T/S
+                     CALL iom_rstput( kt, nitrst, numrow, 'umask'  , umask, ldxios = lwxios ) ! need to correct barotropic velocity
+                     CALL iom_rstput( kt, nitrst, numrow, 'vmask'  , vmask, ldxios = lwxios ) ! need to correct barotropic velocity
+                     CALL iom_rstput( kt, nitrst, numrow, 'smask'  , ssmask, ldxios = lwxios) ! need to correct barotropic velocity
+                     CALL iom_rstput( kt, nitrst, numrow, 'e3t_n', e3t_n(:,:,:), ldxios = lwxios )   ! need to compute temperature correction
+                     CALL iom_rstput( kt, nitrst, numrow, 'e3u_n', e3u_n(:,:,:), ldxios = lwxios )   ! need to compute bt conservation
+                     CALL iom_rstput( kt, nitrst, numrow, 'e3v_n', e3v_n(:,:,:), ldxios = lwxios )   ! need to compute bt conservation
+                     CALL iom_rstput( kt, nitrst, numrow, 'gdepw_n', gdepw_n(:,:,:), ldxios = lwxios ) ! need to compute extrapolation if vvl
+                  END IF
+      ENDIF
+      
+      IF (ln_diurnal) CALL iom_rstput( kt, nitrst, numrow, 'Dsst', x_dsst, ldxios = lwxios )  
+      IF(lwxios) CALL iom_swap(      cxios_context          )
+      IF( kt == nitrst ) THEN
+         IF(.NOT.lwxios) THEN
+            CALL iom_close( numrow )     ! close the restart file (only at last time step)
+         ELSE
+            CALL iom_context_finalize(      cwxios_context          )
+         ENDIF
+!!gm         IF( .NOT. lk_trdmld )   lrst_oce = .FALSE.
+!!gm  not sure what to do here   ===>>>  ask to Sebastian
+         lrst_oce = .FALSE.
+            IF( ln_rst_list ) THEN
+               nrst_lst = MIN(nrst_lst + 1, SIZE(nstocklist,1))
+               nitrst = nstocklist( nrst_lst )
+            ENDIF
+      ENDIF
+      !
+   END SUBROUTINE rst_write
+
+
+   SUBROUTINE rst_read_open
+      !!---------------------------------------------------------------------- 
+      !!                   ***  ROUTINE rst_read_open  ***
+      !! 
+      !! ** Purpose :   Open read files for restart (format fixed by jprstlib )
+      !! 
+      !! ** Method  :   Use a non-zero, positive value of numror to assess whether or not
+      !!                the file has already been opened
+      !!----------------------------------------------------------------------
+      INTEGER        ::   jlibalt = jprstlib
+      LOGICAL        ::   llok
+      CHARACTER(lc)  ::   clpath   ! full path to ocean output restart file
+      !!----------------------------------------------------------------------
+      !
+      IF( numror <= 0 ) THEN
+         IF(lwp) THEN                                             ! Contol prints
+            WRITE(numout,*)
+            SELECT CASE ( jprstlib )
+            CASE ( jpnf90    )   ;   WRITE(numout,*) 'rst_read : read oce NetCDF restart file'
+            END SELECT
+            IF ( snc4set%luse )      WRITE(numout,*) 'rst_read : configured with NetCDF4 support'
+            WRITE(numout,*) '~~~~~~~~'
+         ENDIF
+         lxios_sini = .FALSE.
+         clpath = TRIM(cn_ocerst_indir)
+         IF( clpath(LEN_TRIM(clpath):) /= '/' ) clpath = TRIM(clpath) // '/'
+         CALL iom_open( TRIM(clpath)//cn_ocerst_in, numror, kiolib = jlibalt )
+! are we using XIOS to read the data? Part above will have to modified once XIOS
+! can handle checking if variable is in the restart file (there will be no need to open
+! restart)
+         IF(.NOT.lxios_set) lrxios = lrxios.AND.lxios_sini
+         IF( lrxios) THEN
+             crxios_context = 'nemo_rst'
+             IF( .NOT.lxios_set ) THEN
+                 IF(lwp) WRITE(numout,*) 'Enable restart reading by XIOS'
+                 CALL iom_init( crxios_context )
+                 lxios_set = .TRUE.
+             ENDIF
+         ENDIF
+         IF( TRIM(Agrif_CFixed()) /= '0' .AND. lrxios) THEN
+             CALL iom_init( crxios_context )
+             IF(lwp) WRITE(numout,*) 'Enable restart reading by XIOS for AGRIF'
+             lxios_set = .TRUE.
+         ENDIF 
+      ENDIF
+
+   END SUBROUTINE rst_read_open
+
+
+   SUBROUTINE rst_read
+      !!---------------------------------------------------------------------- 
+      !!                   ***  ROUTINE rst_read  ***
+      !! 
+      !! ** Purpose :   Read files for restart (format fixed by jprstlib )
+      !! 
+      !! ** Method  :   Read in restart.nc file fields which are necessary for restart
+      !!----------------------------------------------------------------------
+      REAL(wp) ::   zrdt
+      INTEGER  ::   jk
+      REAL(wp), DIMENSION(jpi, jpj, jpk) :: w3d
+      !!----------------------------------------------------------------------
+
+      CALL rst_read_open           ! open restart for reading (if not already opened)
+
+      ! Check dynamics and tracer time-step consistency and force Euler restart if changed
+      IF( iom_varid( numror, 'rdt', ldstop = .FALSE. ) > 0 )   THEN
+         CALL iom_get( numror, 'rdt', zrdt, ldxios = lrxios )
+         IF( zrdt /= rdt )   neuler = 0
+      ENDIF
+
+      ! Diurnal DSST 
+      IF( ln_diurnal ) CALL iom_get( numror, jpdom_autoglo, 'Dsst' , x_dsst, ldxios = lrxios ) 
+      IF ( ln_diurnal_only ) THEN 
+         IF(lwp) WRITE( numout, * ) &
+         &   "rst_read:- ln_diurnal_only set, setting rhop=rau0" 
+         rhop = rau0
+         CALL iom_get( numror, jpdom_autoglo, 'tn'     , w3d, ldxios = lrxios ) 
+         tsn(:,:,1,jp_tem) = w3d(:,:,1)
+         RETURN 
+      ENDIF  
+      
+      IF( iom_varid( numror, 'ub', ldstop = .FALSE. ) > 0 ) THEN
+         CALL iom_get( numror, jpdom_autoglo, 'ub'     , ub, ldxios = lrxios                )   ! before fields
+         CALL iom_get( numror, jpdom_autoglo, 'vb'     , vb, ldxios = lrxios                )
+         CALL iom_get( numror, jpdom_autoglo, 'tb'     , tsb(:,:,:,jp_tem), ldxios = lrxios )
+         CALL iom_get( numror, jpdom_autoglo, 'sb'     , tsb(:,:,:,jp_sal), ldxios = lrxios )
+         CALL iom_get( numror, jpdom_autoglo, 'sshb'   , sshb, ldxios = lrxios              )
+      ELSE
+         neuler = 0
+      ENDIF
+      !
+      CALL iom_get( numror, jpdom_autoglo, 'un'     , un, ldxios = lrxios )   ! now    fields
+      CALL iom_get( numror, jpdom_autoglo, 'vn'     , vn, ldxios = lrxios )
+      CALL iom_get( numror, jpdom_autoglo, 'tn'     , tsn(:,:,:,jp_tem), ldxios = lrxios )
+      CALL iom_get( numror, jpdom_autoglo, 'sn'     , tsn(:,:,:,jp_sal), ldxios = lrxios )
+      CALL iom_get( numror, jpdom_autoglo, 'sshn'   , sshn, ldxios = lrxios )
+      IF( iom_varid( numror, 'rhop', ldstop = .FALSE. ) > 0 ) THEN
+         CALL iom_get( numror, jpdom_autoglo, 'rhop'   , rhop, ldxios = lrxios )   ! now    potential density
+      ELSE
+         CALL eos( tsn, rhd, rhop, gdept_n(:,:,:) )   
+      ENDIF
+      !
+      IF( neuler == 0 ) THEN                                  ! Euler restart (neuler=0)
+         tsb  (:,:,:,:) = tsn  (:,:,:,:)                             ! all before fields set to now values
+         ub   (:,:,:)   = un   (:,:,:)
+         vb   (:,:,:)   = vn   (:,:,:)
+         sshb (:,:)     = sshn (:,:)
+         !
+         IF( .NOT.ln_linssh ) THEN
+            DO jk = 1, jpk
+               e3t_b(:,:,jk) = e3t_n(:,:,jk)
+            END DO
+         ENDIF
+         !
+      ENDIF
+      !
+   END SUBROUTINE rst_read
+
+   !!=====================================================================
+END MODULE restart
