2007-01-03 Hans Boehm <Hans.Boehm@hp.com> (based on a patch from

	John Bowman, and an ancient patch from Fergus Henderson)

	* allchblk.c, alloc.c, include/private/gc_priv.h:
	Track GC_bytes_dropped and use in GC triggering decisions.
	* alloc.c (min_bytes_allocd): Weight atomic blocks less.

4 files changed, 17 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index 1623bb5b..d131f806 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2007-01-03  Hans Boehm <Hans.Boehm@hp.com> (based on a patch from
+	John Bowman, and an ancient patch from Fergus Henderson)
+
+	* allchblk.c, alloc.c, include/private/gc_priv.h:
+	Track GC_bytes_dropped and use in GC triggering decisions.
+	* alloc.c (min_bytes_allocd): Weight atomic blocks less.
+
 2007-01-02  Hans Boehm <Hans.Boehm@hp.com>
 
 	* alloc.c (GC_add_to_heap): Call GC_install_header(p) AFTER
diff --git a/allchblk.c b/allchblk.c
index 2be870e9..b3daa591 100644
--- a/allchblk.c
+++ b/allchblk.c
@@ -720,6 +720,7 @@ GC_allochblk_nth(size_t sz, int kind, unsigned flags, int n)
 		      struct hblk * prev = hhdr -> hb_prev;
 	              
 		      GC_large_free_bytes -= total_size;
+		      GC_bytes_dropped += total_size;
 		      GC_remove_from_fl(hhdr, n);
 	              for (h = hbp; h < limit; h++) {
 	                if (h == hbp || 0 != (hhdr = GC_install_header(h))) {
diff --git a/alloc.c b/alloc.c
index f996bff0..5772b2d8 100644
--- a/alloc.c
+++ b/alloc.c
@@ -164,7 +164,7 @@ static word min_bytes_allocd()
     
     if (stack_size < 0) stack_size = -stack_size;
     total_root_size = 2 * stack_size + GC_root_size;
-    scan_size = 2 * GC_composite_in_use + GC_atomic_in_use
+    scan_size = 2 * GC_composite_in_use + GC_atomic_in_use/4
 		+ total_root_size;
     if (TRUE_INCREMENTAL) {
         return scan_size / (2 * GC_free_space_divisor);
@@ -188,6 +188,7 @@ word GC_adj_bytes_allocd(void)
     /* managed object should not alter result, assuming the client	*/
     /* is playing by the rules.						*/
     result = (signed_word)GC_bytes_allocd
+    	     + (signed_word)GC_bytes_dropped
     	     - (signed_word)GC_bytes_freed 
 	     + (signed_word)GC_finalizer_bytes_freed
 	     - expl_managed;
@@ -723,6 +724,7 @@ void GC_finish_collection()
       GC_bytes_allocd_before_gc += GC_bytes_allocd;
       GC_non_gc_bytes_at_gc = GC_non_gc_bytes;
       GC_bytes_allocd = 0;
+      GC_bytes_dropped = 0;
       GC_bytes_freed = 0;
       GC_finalizer_bytes_freed = 0;
       
diff --git a/include/private/gc_priv.h b/include/private/gc_priv.h
index 219adb92..a1e931e5 100644
--- a/include/private/gc_priv.h
+++ b/include/private/gc_priv.h
@@ -862,6 +862,11 @@ struct _GC_arrays {
     word _bytes_allocd;
   	/* Number of words allocated during this collection cycle */
 # endif
+  word _bytes_dropped;
+  	/* Number of black-listed bytes dropped during GC cycle	*/
+	/* as a result of repeated scanning during allocation	*/
+	/* attempts.  These are treated largely as allocated,	*/
+	/* even though they are not useful to the client.	*/
   word _bytes_finalized;
   	/* Approximate number of bytes in objects (and headers)	*/
   	/* That became ready for finalization in the last 	*/
@@ -1039,6 +1044,7 @@ GC_API GC_FAR struct _GC_arrays GC_arrays;
 # define GC_large_free_bytes GC_arrays._large_free_bytes
 # define GC_large_allocd_bytes GC_arrays._large_allocd_bytes
 # define GC_max_large_allocd_bytes GC_arrays._max_large_allocd_bytes
+# define GC_bytes_dropped GC_arrays._bytes_dropped
 # define GC_bytes_finalized GC_arrays._bytes_finalized
 # define GC_non_gc_bytes_at_gc GC_arrays._non_gc_bytes_at_gc
 # define GC_bytes_freed GC_arrays._bytes_freed