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Michael
(This used to be commit 3a4bf4b7c3)

source3/lib/talloc/talloc.c

@@ -792,6 +792,7 @@ void *_talloc_realloc(const void *context, void *ptr, size_t size, const char *n
 		return NULL;
 	}
 
+	/* don't shrink if we have less than 1k to gain */
 	if ((size < tc->size) && ((tc->size - size) < 1024)) {
 		tc->size = size;
 		return ptr;