Merge PPC port

[sbcl.git] / src / code / gc.lisp

diff --git a/src/code/gc.lisp b/src/code/gc.lisp
index d3bcd13..e623c9e 100644 (file)
--- a/src/code/gc.lisp
+++ b/src/code/gc.lisp
@@ -50,10 +50,12 @@
      sb!vm:read-only-space-start))
 
 (defun control-stack-usage ()
-  #!-x86 (- (sb!sys:sap-int (sb!c::control-stack-pointer-sap))
-            sb!vm:control-stack-start)
-  #!+x86 (- sb!vm:control-stack-end
-           (sb!sys:sap-int (sb!c::control-stack-pointer-sap))))
+  #!-stack-grows-downward-not-upward
+  (- (sb!sys:sap-int (sb!c::control-stack-pointer-sap))
+     sb!vm:control-stack-start)
+  #!+stack-grows-downward-not-upward
+  (- sb!vm:control-stack-end
+     (sb!sys:sap-int (sb!c::control-stack-pointer-sap))))
 
 (defun binding-stack-usage ()
   (- (sb!sys:sap-int (sb!c::binding-stack-pointer-sap))
@@ -140,7 +142,14 @@ and submit it as a patch."
 ;;;
 ;;; Unlike CMU CL, we don't export this variable. (There's no need to,
 ;;; since our BYTES-CONSED-BETWEEN-GCS function is SETFable.)
-(defvar *bytes-consed-between-gcs* (* 4 (expt 10 6)))
+(defvar *bytes-consed-between-gcs*
+  #+gencgc (* 4 (expt 10 6))
+  ;; Stop-and-copy GC is really really slow when used too often. CSR
+  ;; reported that even on his old 64 Mb SPARC, 20 Mb is much faster
+  ;; than 4 Mb when rebuilding SBCL ca. 0.7.1. For modern machines
+  ;; with >> 128 Mb memory, the optimum could be significantly more
+  ;; than this, but at least 20 Mb should be better than 4 Mb.
+  #-gencgc (* 20 (expt 10 6)))
 (declaim (type index *bytes-consed-between-gcs*))
 
 ;;;; GC hooks