From d063658d6d233d838429677bdb82dae053492d08 Mon Sep 17 00:00:00 2001
From: Andres Freund <andres@anarazel.de>
Date: Mon, 6 Nov 2017 09:49:32 -0800
Subject: [PATCH] Protect some initializations from being called during backend
 startup.

On EXEC_BACKEND builds these functions shouldn't be called at every
backend start.
---
 src/backend/distributed/shared_library_init.c      |  7 ++++++-
 src/backend/distributed/transaction/backend_data.c |  5 ++++-
 src/backend/distributed/utils/maintenanced.c       |  5 ++++-
 src/backend/distributed/worker/task_tracker.c      | 11 ++++++++---
 4 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/src/backend/distributed/shared_library_init.c b/src/backend/distributed/shared_library_init.c
index 5cc4bc79d..1d2922a25 100644
--- a/src/backend/distributed/shared_library_init.c
+++ b/src/backend/distributed/shared_library_init.c
@@ -170,8 +170,13 @@ _PG_init(void)
 	/*
 	 * Extend the database directory structure before continuing with
 	 * initialization - one of the later steps might require them to exist.
+	 * If in a sub-process (windows / EXEC_BACKEND) this already has been
+	 * done.
 	 */
-	CreateRequiredDirectories();
+	if (!IsUnderPostmaster)
+	{
+		CreateRequiredDirectories();
+	}
 
 	/*
 	 * Register Citus configuration variables. Do so before intercepting
diff --git a/src/backend/distributed/transaction/backend_data.c b/src/backend/distributed/transaction/backend_data.c
index 7356f1cf9..70c08ca8f 100644
--- a/src/backend/distributed/transaction/backend_data.c
+++ b/src/backend/distributed/transaction/backend_data.c
@@ -297,7 +297,10 @@ void
 InitializeBackendManagement(void)
 {
 	/* allocate shared memory */
-	RequestAddinShmemSpace(BackendManagementShmemSize());
+	if (!IsUnderPostmaster)
+	{
+		RequestAddinShmemSpace(BackendManagementShmemSize());
+	}
 
 	prev_shmem_startup_hook = shmem_startup_hook;
 	shmem_startup_hook = BackendManagementShmemInit;
diff --git a/src/backend/distributed/utils/maintenanced.c b/src/backend/distributed/utils/maintenanced.c
index f2e1a2bd8..17c35a08d 100644
--- a/src/backend/distributed/utils/maintenanced.c
+++ b/src/backend/distributed/utils/maintenanced.c
@@ -107,7 +107,10 @@ static bool LockCitusExtension(void);
 void
 InitializeMaintenanceDaemon(void)
 {
-	RequestAddinShmemSpace(MaintenanceDaemonShmemSize());
+	if (!IsUnderPostmaster)
+	{
+		RequestAddinShmemSpace(MaintenanceDaemonShmemSize());
+	}
 
 	prev_shmem_startup_hook = shmem_startup_hook;
 	shmem_startup_hook = MaintenanceDaemonShmemInit;
diff --git a/src/backend/distributed/worker/task_tracker.c b/src/backend/distributed/worker/task_tracker.c
index 48a6ec6c5..d5dfe89fe 100644
--- a/src/backend/distributed/worker/task_tracker.c
+++ b/src/backend/distributed/worker/task_tracker.c
@@ -100,12 +100,17 @@ TaskTrackerRegister(void)
 {
 	BackgroundWorker worker;
 
-	/* organize and register initialization of required shared memory */
-	RequestAddinShmemSpace(TaskTrackerShmemSize());
-
 	prev_shmem_startup_hook = shmem_startup_hook;
 	shmem_startup_hook = TaskTrackerShmemInit;
 
+	if (IsUnderPostmaster)
+	{
+		return;
+	}
+
+	/* organize and register initialization of required shared memory */
+	RequestAddinShmemSpace(TaskTrackerShmemSize());
+
 	/* and that the task tracker is started as background worker */
 	memset(&worker, 0, sizeof(worker));
 	worker.bgw_flags = BGWORKER_SHMEM_ACCESS;