OTP-8240 Improved GC performance after BIF/NIF call when a lot of heap

          fragments was created. This will mainly benefit NIFs that return
          large compound terms.

1 files changed, 24 insertions, 6 deletions

diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h
index 7597eb5e31..1f841b2113 100644
--- a/erts/emulator/beam/erl_process.h
+++ b/erts/emulator/beam/erl_process.h
@@ -1,19 +1,19 @@
 /*
  * %CopyrightBegin%
- * 
- * Copyright Ericsson AB 1996-2009. All Rights Reserved.
- * 
+ *
+ * Copyright Ericsson AB 1996-2010. All Rights Reserved.
+ *
  * The contents of this file are subject to the Erlang Public License,
  * Version 1.1, (the "License"); you may not use this file except in
  * compliance with the License. You should have received a copy of the
  * Erlang Public License along with this software. If not, it can be
  * retrieved online at http://www.erlang.org/.
- * 
+ *
  * Software distributed under the License is distributed on an "AS IS"
  * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
  * the License for the specific language governing rights and limitations
  * under the License.
- * 
+ *
  * %CopyrightEnd%
  */
 
@@ -654,6 +654,11 @@ struct process {
 				 * heap fragments.
 				 */
 #endif
+
+#ifdef FORCE_HEAP_FRAGS
+    Uint space_verified;        /* Avoid HAlloc forcing heap fragments when */ 
+    Eterm* space_verified_from; /* we rely on available heap space (TestHeap) */
+#endif
 };
 
 #ifdef CHECK_FOR_HOLES
@@ -738,7 +743,20 @@ typedef struct {
 
 #define KILL_CATCHES(p) (p)->catches = -1
 
-void erts_arith_shrink(Process* p, Eterm* hp);
+/* Shrink heap fragment from _last_ HAlloc.
+*/
+ERTS_GLB_INLINE void erts_heap_frag_shrink(Process* p, Eterm* hp);
+#if ERTS_GLB_INLINE_INCL_FUNC_DEF
+ERTS_GLB_INLINE void erts_heap_frag_shrink(Process* p, Eterm* hp)
+{
+    ErlHeapFragment* hf = MBUF(p);
+
+    ASSERT(hf!=NULL && (hp - hf->mem < (unsigned long)hf->size));
+
+    hf->used_size = hp - hf->mem;
+}	
+#endif /* inline */
+
 Eterm* erts_heap_alloc(Process* p, Uint need);
 #ifdef CHECK_FOR_HOLES
 Eterm* erts_set_hole_marker(Eterm* ptr, Uint sz);