Set cpu affinity

src/server.c

@@ -188,6 +188,7 @@ gboolean server_loop_init(server *srv) {
 	if (srv->worker_count < 1) srv->worker_count = 1;
 	g_array_set_size(srv->workers, srv->worker_count);
 	srv->main_worker = g_array_index(srv->workers, worker*, 0) = worker_new(srv, loop);
+	srv->main_worker->ndx = 0;
 	for (i = 1; i < srv->worker_count; i++) {
 		GError *error = NULL;
 		worker *wrk;
@@ -196,6 +197,7 @@ gboolean server_loop_init(server *srv) {
 			return FALSE;
 		}
 		wrk = g_array_index(srv->workers, worker*, i) = worker_new(srv, loop);
+		wrk->ndx = i;
 		if (NULL == (wrk->thread = g_thread_create(server_worker_cb, wrk, TRUE, &error))) {
 			g_error ( "g_thread_create failed: %s", error->message );
 			return FALSE;

src/worker.c

@@ -1,4 +1,6 @@
 
+#include <sched.h>
+
 #include "base.h"
 
 void con_put(connection *con);
@@ -200,6 +202,23 @@ void worker_free(worker *wrk) {
 }
 
 void worker_run(worker *wrk) {
+	cpu_set_t mask;
+
+	if (0 != sched_getaffinity(0, sizeof(mask), &mask)) {
+		ERROR(wrk->srv, "couldn't get cpu affinity mask: %s", g_strerror(errno));
+	} else {
+		guint cpus = 0;
+		while (CPU_ISSET(cpus, &mask)) cpus++;
+		if (cpus) {
+			CPU_ZERO(&mask);
+			CPU_SET(wrk->ndx % cpus, &mask);
+			if (0 != sched_setaffinity(0, sizeof(mask), &mask)) {
+				ERROR(wrk->srv, "couldn't set cpu affinity mask: %s", g_strerror(errno));
+			}
+		} else {
+			ERROR(wrk->srv, "%s", "cpu 0 not enabled, no affinity set");
+		}
+	}
 	ev_loop(wrk->loop, 0);
 }
 

src/worker.h

@@ -20,6 +20,7 @@ struct worker {
 	struct server *srv;
 
 	GThread *thread; /* managed by server.c */
+	guint ndx;       /* worker index */
 
 	struct ev_loop *loop;
 	ev_prepare loop_prepare;