Changeset 12060 for source/ariba/overlay/modules/chord/detail

Timestamp:

Jun 19, 2013, 11:05:49 AM (11 years ago)

Author:

hock@…

Message:

Reintegrate branch: 20130111-hock-message_classes

improvements:

• new message classes (reboost, zero-copy)
• "fast path" for direct links (skip overlay layer)
• link-properties accessible from the application
• SystemQueue can call boost::bind functions
• protlib compatibility removed (32bit overhead saved in every message)
• addressing2
• AddressDiscovery discoveres only addresses on which we're actually listening
• ariba serialization usage reduced (sill used in OverlayMsg)
• Node::connect, easier and cleaner interface to start-up ariba from the application
• ariba configs via JSON, XML, etc (boost::property_tree)
• keep-alive overhead greatly reduced
• (relayed) overlay links can actually be closed now
• lost messages are detected in most cases
• notification to the application when link is transformed into direct-link
• overlay routing: send message to second best hop if it would be dropped otherwise
• SequenceNumbers (only mechanisms, so for: upward compatibility)
• various small fixes

regressions:

• bluetooth is not yet working again
• bootstrap modules deactivated
• liblog4xx is not working (use cout-logging)

This patch brings great performance and stability improvements at cost of backward compatibility.
Also bluetooth and the bootstrap modules have not been ported to the new interfaces, yet.

File:

• source/ariba/overlay/modules/chord/detail/chord_routing_table.hpp (modified) (3 diffs)

source/ariba/overlay/modules/chord/detail/chord_routing_table.hpp

@@ -96 +96 @@
         // the own node id
         nodeid_t id;
+    
+    // the own node id as routing item
+    item own_id_item;
 
         // successor and predecessor tables
@@ -168 +171 @@
         /// constructs the reactive chord routing table
         explicit chord_routing_table( const nodeid_t& id, int redundancy = 4 ) :
-                id(id), succ( redundancy, succ_compare_type(this->id), *this ),
-                pred( redundancy, pred_compare_type(this->id), *this ) {
+                id(id),
+                succ( redundancy, succ_compare_type(this->id), *this ),
+                pred( redundancy, pred_compare_type(this->id), *this )
+    {
+        // init reflexive item
+        own_id_item.id = id;
+        own_id_item.ref_count = 1;
 
                 // create finger tables
@@ -273 +281 @@
                         }
                 }
+
                 if (best_item != NULL && distance(value, id)<distance(value, best_item->id))
                         return NULL;
                 return best_item;
         }
+        
+        std::vector<const item*> get_next_2_hops( const nodeid_t& value)
+    {
+        ring_distance distance;
+        item* best_item = &own_id_item;
+        item* second_best_item = NULL;
+        
+        // find best and second best item
+        for (size_t i=0; i<table.size(); i++)
+        {
+            item* curr = &table[i];
+
+            // not not include orphans into routing!
+            if (curr->ref_count==0) continue;
+
+            // check if we found a better item
+            // is best item
+            if ( distance(value, curr->id) < distance(value, best_item->id) )
+            {
+                second_best_item = best_item;
+                best_item = curr;
+            }
+            // is second best item
+            else
+            {
+                if ( second_best_item == NULL )
+                {
+                    second_best_item = curr;
+                    continue;
+                }
+                
+                if ( distance(value, curr->id) < distance(value, second_best_item->id) )
+                {
+                    second_best_item = curr;
+                }
+            }
+        }
+
+        // prepare return vector
+        std::vector<const item*> ret;
+        if ( best_item != NULL )
+        {
+            ret.push_back(best_item);
+        }
+        if ( second_best_item != NULL )
+        {
+            ret.push_back(second_best_item);
+        }
+        
+        return ret;
+    }
 
         const nodeid_t* get_successor() {
-                if (succ.size()==NULL) return NULL;
+                if (succ.size()==0) return NULL;
                 return &succ.front();
         }
 
         const nodeid_t* get_predesessor() {
-                if (pred.size()==NULL) return NULL;
+                if (pred.size()==0) return NULL;
                 return &pred.front();
         }