From: Simon Riggs <simon@2ndQuadrant.com>
Date: Thu, 29 Nov 2012 23:52:17 +0000 (+0000)
Subject: Correctly init/deinit recovery xact environment.
X-Git-Tag: REL9_1_7~18
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=6f9a9da85c9015e773d12e8571c469e5a2a6b3fb;p=postgresql

Correctly init/deinit recovery xact environment.
Previously we performed VirtualXactLockTableInsert
but didn't set MyProc->lxid for Startup process.
pg_locks now correctly shows "1/1" for vxid
of Startup process during Hot Standby.
At end of Hot Standby the Virtual Transaction
was not deleted, leading to problems after
promoting to normal running for some commands,
such as CREATE INDEX CONCURRENTLY.
---

diff --git a/src/backend/storage/ipc/standby.c b/src/backend/storage/ipc/standby.c
index fdec0eb225..e1a9fbb726 100644
--- a/src/backend/storage/ipc/standby.c
+++ b/src/backend/storage/ipc/standby.c
@@ -81,7 +81,7 @@ InitRecoveryTransactionEnvironment(void)
 	 * hold AccessShareLocks so never block while we write or lock new rows.
 	 */
 	vxid.backendId = MyBackendId;
-	vxid.localTransactionId = GetNextLocalTransactionId();
+	vxid.localTransactionId = MyProc->lxid = GetNextLocalTransactionId();
 	VirtualXactLockTableInsert(vxid);
 
 	standbyState = STANDBY_INITIALIZED;
@@ -97,11 +97,18 @@ InitRecoveryTransactionEnvironment(void)
 void
 ShutdownRecoveryTransactionEnvironment(void)
 {
+	VirtualTransactionId vxid;
+
 	/* Mark all tracked in-progress transactions as finished. */
 	ExpireAllKnownAssignedTransactionIds();
 
 	/* Release all locks the tracked transactions were holding */
 	StandbyReleaseAllLocks();
+
+	/* Cleanup our VirtualTransaction */
+	vxid.backendId = MyBackendId;
+	vxid.localTransactionId = MyProc->lxid;
+	VirtualXactLockTableDelete(vxid);
 }
 
 
diff --git a/src/backend/storage/lmgr/lmgr.c b/src/backend/storage/lmgr/lmgr.c
index 859b3852db..f49222e69d 100644
--- a/src/backend/storage/lmgr/lmgr.c
+++ b/src/backend/storage/lmgr/lmgr.c
@@ -534,6 +534,24 @@ VirtualXactLockTableInsert(VirtualTransactionId vxid)
 	(void) LockAcquire(&tag, ExclusiveLock, false, false);
 }
 
+/*
+ *		VirtualXactLockTableDelete
+ *
+ * Release a Virtual Transaction lock. Only called by Startup process
+ * at end of Hot Standby.
+ */
+void
+VirtualXactLockTableDelete(VirtualTransactionId vxid)
+{
+	LOCKTAG		tag;
+
+	Assert(VirtualTransactionIdIsValid(vxid));
+
+	SET_LOCKTAG_VIRTUALTRANSACTION(tag, vxid);
+
+	(void) LockRelease(&tag, ExclusiveLock, false);
+}
+
 /*
  *		VirtualXactLockTableWait
  *
diff --git a/src/include/storage/lmgr.h b/src/include/storage/lmgr.h
index bd44d92be3..23cb5aee46 100644
--- a/src/include/storage/lmgr.h
+++ b/src/include/storage/lmgr.h
@@ -58,6 +58,7 @@ extern bool ConditionalXactLockTableWait(TransactionId xid);
 
 /* Lock a VXID (used to wait for a transaction to finish) */
 extern void VirtualXactLockTableInsert(VirtualTransactionId vxid);
+extern void VirtualXactLockTableDelete(VirtualTransactionId vxid);
 extern void VirtualXactLockTableWait(VirtualTransactionId vxid);
 extern bool ConditionalVirtualXactLockTableWait(VirtualTransactionId vxid);