improve perNeighborSendQueue

- improve shuffling between rows and columns
- speed up code execution

Signed-off-by: Csaba Kiraly <csaba.kiraly@gmail.com>

DAS/validator.py

@@ -142,6 +142,7 @@ class Validator:
         self.repairOnTheFly = True
         self.sendLineUntil = (self.shape.blockSize + 1) // 2 # stop sending on a p2p link if at least this amount of samples passed
         self.perNeighborQueue = True # queue incoming messages to outgoing connections on arrival (as typical GossipSub impl)
+        self.shuffleQueues = True # shuffle the order of picking from active queues of a sender node
         self.perNodeQueue = False # keep a global queue of incoming messages for later sequential dispatch
         self.shuffleLines = True # shuffle the order of rows/columns in each iteration while trying to send
         self.shuffleNeighbors = True # shuffle the order of neighbors when sending the same segment to each neighbor
@@ -294,21 +295,27 @@ class Validator:
         progress = True
         while (progress):
             progress = False
-            for rID, neighs in shuffledDict(self.rowNeighbors, self.shuffleLines):
-                for _, neigh in shuffledDict(neighs, self.shuffleNeighbors):
-                    if (neigh.sendQueue):
-                        self.sendSegmentToNeigh(rID, neigh.sendQueue.popleft(), neigh)
-                        progress = True
-                    if self.statsTxInSlot >= self.bwUplink:
-                        return
 
-            for cID, neighs in shuffledDict(self.columnNeighbors, self.shuffleLines):
-                for _, neigh in shuffledDict(neighs, self.shuffleNeighbors):
+            queues = []
+            # collect and shuffle
+            for rID, neighs in self.rowNeighbors.items():
+                for neigh in neighs.values():
                     if (neigh.sendQueue):
-                        self.sendSegmentToNeigh(neigh.sendQueue.popleft(), cID, neigh)
-                        progress = True
-                    if self.statsTxInSlot >= self.bwUplink:
-                        return
+                        queues.append((0, rID, neigh))
+
+            for cID, neighs in self.columnNeighbors.items():
+                for neigh in neighs.values():
+                    if (neigh.sendQueue):
+                        queues.append((1, cID, neigh))
+
+            for dim, lineID, neigh in shuffled(queues, self.shuffleQueues):
+                if dim == 0:
+                    self.sendSegmentToNeigh(lineID, neigh.sendQueue.popleft(), neigh)
+                else:
+                    self.sendSegmentToNeigh(neigh.sendQueue.popleft(), lineID, neigh)
+                progress = True
+                if self.statsTxInSlot >= self.bwUplink:
+                    return
 
     def runSegmentShuffleScheduler(self):
             # This scheduler check which owned segments needs sending (at least