PGPRO-1238 fix recovery of prepared tranasctions in minor node

Author: knizhnik

multimaster.c

@@ -1707,8 +1707,27 @@ static void MtmBroadcastPollMessage(MtmTransState* ts)
 
 	if (nparts == 1)
 	{
-		/* we were in major mode and there nobody to ask about status */
-		MtmFinishPreparedTransaction(ts, true);
+		int refereeWinnerId = MtmRefereeReadSaved();
+		if (MtmMajorNode || refereeWinnerId == MtmNodeId)
+		{
+			MTM_ELOG(LOG, "%s node commits prepared transaction %s", MtmMajorNode ? "Major" : "Winner", ts->gid);
+			/* we were in major mode and there nobody to ask about status */
+			MtmFinishPreparedTransaction(ts, true);
+		}
+		else
+		{
+			int coordinator = 0;
+			sscanf(ts->gid, "MTM-%d", &coordinator);
+			if (coordinator == MtmNodeId && ts->status == TRANSACTION_STATUS_IN_PROGRESS) {
+				/* it is always safe to rollback self transaction which was not precommitted: it can not be committed anywhere else */
+				MTM_ELOG(LOG, "Coordinator node rollback not precommitted transaction %s", ts->gid);
+				MtmFinishPreparedTransaction(ts, false);
+			}
+			else
+			{
+				MTM_ELOG(WARNING, "Doesn't know waht to do with transaction prepared transaction %s", ts->gid);
+			}
+		}
 		return;
 	}
 

state.c

@@ -31,7 +31,6 @@ char const* const MtmEventMnem[] =
 
 static int  MtmRefereeGetWinner(void);
 static bool MtmRefereeClearWinner(void);
-static int  MtmRefereeReadSaved(void);
 
 static bool mtm_state_initialized;
 
@@ -586,7 +585,7 @@ MtmRefereeHasLocalTable()
 	return OidIsValid(rel_oid);
 }
 
-static int
+int
 MtmRefereeReadSaved(void)
 {
 	int winner = -1;

state.h

@@ -30,9 +30,11 @@ extern void MtmOnNodeDisconnect(int nodeId);
 extern void MtmOnNodeConnect(int nodeId);
 extern void MtmReconnectNode(int nodeId);
 
+extern int  MtmRefereeReadSaved(void);
+
 extern void MtmRefreshClusterStatus(void);
 
 extern int countZeroBits(nodemask_t mask, int nNodes);
 
 extern MtmNodeStatus MtmGetCurrentStatus(void);
-extern nodemask_t MtmGetDisabledNodeMask(void);
+extern nodemask_t MtmGetDisabledNodeMask(void);

tests/makefile

@@ -1,13 +1,17 @@
 CXX=g++
-CXXFLAGS=-g -Wall -O0 -pthread 
+CC=gcc
+CFLAGS=-g -Wall -O0 -pthread 
 
-all: dtmbench dtmacid
+all: dtmbench dtmacid insert
 
 dtmbench: dtmbench.cpp
-	$(CXX) $(CXXFLAGS) -o dtmbench dtmbench.cpp -lpqxx -lpq
+	$(CXX) $(CFLAGS) -o dtmbench dtmbench.cpp -lpqxx -lpq
 
 dtmacid: dtmacid.cpp
-	$(CXX) $(CXXFLAGS) -o dtmacid dtmacid.cpp -lpqxx -lpq
+	$(CXX) $(CFLAGS) -o dtmacid dtmacid.cpp -lpqxx -lpq
+
+insert: insert.c
+	$(CC) $(CFLAGS) -o insert insert.c -lpq
 
 clean:
 	rm -f dtmbench dtmacid