2 files changed, 40 insertions, 0 deletions
diff --git a/src/include/pg_config_manual.h b/src/include/pg_config_manual.h
index 3cbdc6d180e..d27c8601fa7 100644
--- a/src/include/pg_config_manual.h
+++ b/src/include/pg_config_manual.h
@@ -310,6 +310,45 @@
 /* #define RANDOMIZE_ALLOCATED_MEMORY */
 
 /*
+ * For cache invalidation debugging, define CLOBBER_CACHE_ENABLED to enable
+ * use of the debug_invalidate_system_caches_always GUC to aggressively flush
+ * syscache/relcache entries whenever it's possible to deliver invalidations.
+ * See AcceptInvalidationMessages() in src/backend/utils/cache/inval.c for
+ * details.
+ *
+ * USE_ASSERT_CHECKING builds default to enabling this.  It's possible to use
+ * CLOBBER_CACHE_ENABLED without a cassert build and the implied
+ * CLOBBER_FREED_MEMORY and MEMORY_CONTEXT_CHECKING options but it's unlikely
+ * to be as effective at identifying problems.
+ */
+/* #define CLOBBER_CACHE_ENABLED */
+
+#if defined(USE_ASSERT_CHECKING) && !defined(CLOBBER_CACHE_ENABLED)
+#define CLOBBER_CACHE_ENABLED
+#endif
+
+/*
+ * Backwards compatibility for the older compile-time-only cache clobber
+ * macros.
+ */
+#if !defined(CLOBBER_CACHE_ENABLED) && (defined(CLOBBER_CACHE_ALWAYS) || defined(CLOBBER_CACHE_RECURSIVELY))
+#define CLOBBER_CACHE_ENABLED
+#endif
+
+/*
+ * Recover memory used for relcache entries when invalidated.  See
+ * RelationBuildDescr() in src/backend/utils/cache/relcache.c.
+ *
+ * This is active automatically for clobber cache builds when clobbering is
+ * active, but can be overridden here by explicitly defining
+ * RECOVER_RELATION_BUILD_MEMORY.  Define to 1 to always free relation cache
+ * memory even when clobber is off, or to 0 to never free relation cache
+ * memory even when clobbering is on.
+ */
+/* #define RECOVER_RELATION_BUILD_MEMORY 0 */ /* Force disable */
+/* #define RECOVER_RELATION_BUILD_MEMORY 1 */ /* Force enable */
+
+/*
  * Define this to force all parse and plan trees to be passed through
  * copyObject(), to facilitate catching errors and omissions in
  * copyObject().
diff --git a/src/include/utils/inval.h b/src/include/utils/inval.h
index 49ae5d28646..a7e04722d01 100644
--- a/src/include/utils/inval.h
+++ b/src/include/utils/inval.h
@@ -18,6 +18,7 @@
 #include "storage/relfilenode.h"
 #include "utils/relcache.h"
 
+extern PGDLLIMPORT int debug_invalidate_system_caches_always;
 
 typedef void (*SyscacheCallbackFunction) (Datum arg, int cacheid, uint32 hashvalue);
 typedef void (*RelcacheCallbackFunction) (Datum arg, Oid relid);