Creating a group from PMIx
The Process Management Interface for Exascale (PMIx) provides
another way of bootstraping an SSG group. The following code
sample illustrates how to do so using the ssg_group_create_pmix
function.
main.c (show/hide)
#include <mpi.h>
#include <assert.h>
#include <stdio.h>
#include <ssg.h>
#include <ssg-pmix.h>
static void my_membership_update_cb(void* uargs,
ssg_member_id_t member_id,
ssg_member_update_type_t update_type)
{
switch(update_type) {
case SSG_MEMBER_JOINED:
printf("Member %ld joined\n", member_id);
break;
case SSG_MEMBER_LEFT:
printf("Member %ld left\n", member_id);
break;
case SSG_MEMBER_DIED:
printf("Member %ld died\n", member_id);
break;
}
}
int main(int argc, char** argv)
{
pmix_proc_t proc;
PMIx_Init(&proc, NULL, 0);
margo_instance_id mid = margo_init("tcp", MARGO_SERVER_MODE, 1, 0);
assert(mid);
int ret = ssg_init();
assert(ret == SSG_SUCCESS);
ssg_group_config_t config = {
.swim_period_length_ms = 1000,
.swim_suspect_timeout_periods = 5,
.swim_subgroup_member_count = -1,
.swim_disabled = 0,
.ssg_credential = -1
};
ssg_group_id_t gid;
ret = ssg_group_create_pmix(
mid, "mygroup", proc,
&config, my_membership_update_cb, NULL, &gid);
// ...
// do stuff using the group
// ...
ret = ssg_group_leave(gid);
assert(ret == SSG_SUCCESS);
ret = ssg_group_destroy(gid);
assert(ret == SSG_SUCCESS);
ret = ssg_finalize();
assert(ret == SSG_SUCCESS);
margo_finalize(mid);
PMIx_Finalize(NULL, 0);
return 0;
}