Revert scheduling back to use real-time processes

[sahlberg/ctdb.git] / common / ctdb_util.c

diff --git a/common/ctdb_util.c b/common/ctdb_util.c
index c705249549d8e3b0da7dcb1dea62e7f1cfd0a157..80390899c7f46e0753e48fa6bbb3a0c3f541353f 100644 (file)
--- a/common/ctdb_util.c
+++ b/common/ctdb_util.c
@@ -285,19 +285,52 @@ struct ctdb_rec_data *ctdb_marshall_loop_next(struct ctdb_marshall_buffer *m, st
        return r;
 }
 
+
+#if HAVE_SCHED_H
+#include <sched.h>
+#endif
+
 /*
-  if possible, make this task very high priority
+  if possible, make this task real time
  */
-void ctdb_high_priority(struct ctdb_context *ctdb)
+void ctdb_set_scheduler(struct ctdb_context *ctdb)
 {
-       errno = 0;
-       if (nice(-20) == -1 && errno != 0) {
-               DEBUG(DEBUG_WARNING,("Unable to renice self: %s\n",
-                                    strerror(errno)));
+#if HAVE_SCHED_SETSCHEDULER    
+       struct sched_param p;
+       if (ctdb->saved_scheduler_param == NULL) {
+               ctdb->saved_scheduler_param = talloc_size(ctdb, sizeof(p));
+       }
+       
+       if (sched_getparam(0, (struct sched_param *)ctdb->saved_scheduler_param) == -1) {
+               DEBUG(DEBUG_ERR,("Unable to get old scheduler params\n"));
+               return;
+       }
+
+       p = *(struct sched_param *)ctdb->saved_scheduler_param;
+       p.sched_priority = 1;
+
+       if (sched_setscheduler(0, SCHED_FIFO, &p) == -1) {
+               DEBUG(DEBUG_CRIT,("Unable to set scheduler to SCHED_FIFO (%s)\n", 
+                        strerror(errno)));
        } else {
-               DEBUG(DEBUG_NOTICE,("Scheduler says I'm nice: %i\n",
-                                   getpriority(PRIO_PROCESS, getpid())));
+               DEBUG(DEBUG_NOTICE,("Set scheduler to SCHED_FIFO\n"));
+       }
+#endif
+}
+
+/*
+  restore previous scheduler parameters
+ */
+void ctdb_restore_scheduler(struct ctdb_context *ctdb)
+{
+#if HAVE_SCHED_SETSCHEDULER    
+       if (ctdb->saved_scheduler_param == NULL) {
+               ctdb_fatal(ctdb, "No saved scheduler parameters\n");
        }
+       if (sched_setscheduler(0, SCHED_OTHER, (struct sched_param *)ctdb->saved_scheduler_param) == -1) {
+               ctdb_fatal(ctdb, "Unable to restore old scheduler parameters\n");
+       }
+#endif
 }
 
 /*