petsc-3.10.5 2019-03-28

PetscSFGetWindow

Get a window for use with a given data type

Synopsis

#include "petscsf.h" 
static PetscErrorCode PetscSFGetWindow(PetscSF sf,MPI_Datatype unit,void *array,PetscBool epoch,PetscMPIInt fenceassert,PetscMPIInt postassert,PetscMPIInt startassert,MPI_Win *win)

Collective on PetscSF

Input Arguments

	sf	- star forest
	unit	- data type
	array	- array to be sent
	epoch	- PETSC_TRUE to acquire the window and start an epoch, PETSC_FALSE to just acquire the window
	fenceassert	- assert parameter for call to MPI_Win_fence(), if PETSCSF_WINDOW_SYNC_FENCE
	postassert	- assert parameter for call to MPI_Win_post(), if PETSCSF_WINDOW_SYNC_ACTIVE
	startassert	- assert parameter for call to MPI_Win_start(), if PETSCSF_WINDOW_SYNC_ACTIVE

Output Arguments

win -window

Developer Notes

This currently always creates a new window. This is more synchronous than necessary. An alternative is to try to reuse an existing window created with the same array. Another alternative is to maintain a cache of windows and reuse whichever one is available, by copying the array into it if necessary.

Level

developer

Location

src/vec/is/sf/impls/window/sfwindow.c
Index of all PetscSF routines
Table of Contents for all manual pages
Index of all manual pages