Ascertain the Number of CPUs in the Resource Pool

sysconf(3C) provides information about the number of CPUs on an entire system. The following example provides the granularity of ascertaining the number of CPUs that are defined in a particular application's pools pset.

The key points for this example include the following:

• pvals[] should be a NULL terminated array.

• pool_query_pool_resources() returns a list of all resources that match the pvals array type pset from the application's pool my_pool. Because a pool can have only one instance of the pset resource, each instance is always returned in nelem. reslist[] contains only one element, the pset resource.

pool_value_t *pvals[2] = {NULL};  /* pvals[] should be NULL terminated */

/* NOTE: Return value checking/error processing omitted */
/* in all examples for brevity */

conf_loc = pool_dynamic_location();
conf = pool_conf_alloc();
pool_conf_open(conf, conf_loc, PO_RDONLY);
my_pool_name = pool_get_binding(getpid());
my_pool = pool_get_pool(conf, my_pool_name);
pvals[0] = pool_value_alloc();
pvals2[2] = { NULL, NULL };
pool_value_set_name(pvals[0], "type");
pool_value_set_string(pvals[0], "pset");

reslist = pool_query_pool_resources(conf, my_pool, &nelem, pvals);
pool_value_free(pvals[0]);
pool_query_resource_components(conf, reslist[0], &nelem, NULL);
printf("pool %s: %u cpu", my_pool_ name, nelem);
pool_conf_close(conf);