SHMEM_FENCE(3)

💅 SHMEM_FENCE(3) — Open MPI manual page, bestie 💅

okay so bestie, this is the SHMEM_FENCE(3) page straight outta Open MPI, and it's all about fencing your puts. not like a garden fence, like an ordering fence, iykyk. let's go 💖

🌸 NAME 🌸

shmem_fence — provides a separate ordering on the sequence of puts issued by this PE to each destination PE. 🫶

✨ SYNOPSIS ✨

C or C++:

#include <mpp/shmem.h>

void shmem_fence(void)

Fortran:

INCLUDE "mpp/shmem.fh"

CALL SHMEM_FENCE

💖 DESCRIPTION 💖

okay so the shmem_fence() routine gives you an ordering on the put operations issued by the calling PE before the call to shmem_fence() relative to the put operations issued by the calling PE after the call to shmem_fence(). 🎀

It guarantees that all such prior put operations issued to a particular destination PE are fully written to the symmetric memory of that destination PE before any such following put operations to that same destination PE are written to the symmetric memory of that destination PE. literally the whole point, no cap. ✨

Note that the ordering is provided separately on the sequences of puts from the calling PE to each distinct destination PE. it's giving separate ordering for each distinct destination PE. 🌈

The shmem_quiet() routine should be used instead if ordering of puts is required when multiple destination PEs are involved. periodt. 💅

🎀 NOTES 🎀

The shmem_quiet function should be called if ordering of puts is desired when multiple remote PEs are involved. 🫶

🦋 SEE ALSO 🦋

• intro_shmem(3)

📜 COPYRIGHT 📜

2003-2026, The Open MPI Community

and that's the whole page, bestie 💖 — source/version: Open MPI, dated May 14, 2026. mwah 💋