Changeset 563:dc9764591567 in freeDiameter

Timestamp:

Sep 16, 2010, 4:41:44 PM (14 years ago)

Author:

Sebastien Decugis <sdecugis@nict.go.jp>

Branch:

default

Phase:

public

Message:

Automatic load-balancing between peers that have the same routing score. Use rt_ereg to obtain stable routes.

Files:

• freeDiameter/routing_dispatch.c (modified) (1 diff)
• libfreeDiameter/rt_data.c (modified) (2 diffs)

freeDiameter/routing_dispatch.c

@@ -844 +844 @@
                 CHECK_FCT( fd_rtd_init(&rtd) );
 
-                /* Add all peers in OPEN state */
+                /* Add all peers currently in OPEN state */
                 CHECK_FCT( pthread_rwlock_rdlock(&fd_g_activ_peers_rw) );
                 for (li = fd_g_activ_peers.next; li != &fd_g_activ_peers; li = li->next) {

libfreeDiameter/rt_data.c

@@ -250 +250 @@
 }
 
-/* Reorder the list of peers */
+/* Reorder the list of peers. If several peer have the same highest score, they are randomized. */
 int  fd_rtd_candidate_reorder(struct fd_list * candidates)
 {
         struct fd_list unordered = FD_LIST_INITIALIZER(unordered), *li;
+        struct fd_list highest = FD_LIST_INITIALIZER(highest);
+        int hs = -1;
         
         TRACE_ENTRY("%p", candidates);
@@ -267 +269 @@
                 fd_list_unlink(&c->chain);
                 
-                /* Find the position in ordered candidates list */
-                for (li = candidates->next; li != candidates; li = li->next) {
-                        struct rtd_candidate * cnext = (struct rtd_candidate *) li;
-                        if (cnext->score >= c->score)
-                                break;
-                }
-                
-                /* Add the element there */
-                fd_list_insert_before(li, &c->chain);
-        }
+                /* If this candidate has a higher score than the previous ones */
+                if (c->score > hs) {
+                        /* Then we move the previous high score items at end of the list */
+                        fd_list_move_end(candidates, &highest);
+                        
+                        /* And the new high score is this reset */
+                        hs = c->score;
+                }
+                
+                /* If this candidate equals the higher score, add it into highest list at a random place */
+                if (c->score == hs) {
+                        if (rand() & 1) {
+                                fd_list_insert_after(&highest, &c->chain);
+                        } else {
+                                fd_list_insert_before(&highest, &c->chain);
+                        }
+                /* Otherwise, insert at normal place in the list */
+                } else {
+                        /* Find the position in ordered candidates list */
+                        for (li = candidates->next; li != candidates; li = li->next) {
+                                struct rtd_candidate * cnext = (struct rtd_candidate *) li;
+                                if (cnext->score >= c->score)
+                                        break;
+                        }
+
+                        /* Add the element there */
+                        fd_list_insert_before(li, &c->chain);
+                }
+        }
+        
+        /* Now simply move back all the "highest" candidates at the end of the list */
+        fd_list_move_end(candidates, &highest);
         
         return 0;