X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Fgc.lisp;h=523f347bf147e729f601cfc125f71c16f0c0d911;hb=4dbc52ee4f9a4f566701f1d33e7916e8491b918b;hp=5ed0b353cfd5a324a9a8fc9987df564a4be4ede6;hpb=bde2d08778488aba0ff0c30bc0afb17fbdacb4e4;p=sbcl.git diff --git a/src/code/gc.lisp b/src/code/gc.lisp index 5ed0b35..523f347 100644 --- a/src/code/gc.lisp +++ b/src/code/gc.lisp @@ -42,18 +42,20 @@ (current-dynamic-space-start)))) (defun static-space-usage () - (- (* sb!vm:*static-space-free-pointer* sb!vm:word-bytes) + (- (* sb!vm:*static-space-free-pointer* sb!vm:n-word-bytes) sb!vm:static-space-start)) (defun read-only-space-usage () - (- (* sb!vm::*read-only-space-free-pointer* sb!vm:word-bytes) + (- (* sb!vm::*read-only-space-free-pointer* sb!vm:n-word-bytes) 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)) @@ -74,7 +76,7 @@ (room-minimal-info) (sb!vm:memory-usage :count-spaces '(:dynamic) :print-spaces t - :cutoff 0.05s0 + :cutoff 0.05f0 :print-summary nil)) (defun room-maximal-info () @@ -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* (* 2 (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 @@ -170,25 +179,49 @@ and submit it as a patch." ;;; a limit to help catch programs which allocate too much memory, ;;; since a hard heap overflow is so hard to recover from +;;; +;;; FIXME: Like *GC-TRIGGER*, this variable (1) should probably be +;;; denominated in a larger unit than bytes and (2) should probably be +;;; renamed so that it's clear from the name what unit it's +;;; denominated in. (declaim (type (or unsigned-byte null) *soft-heap-limit*)) -(defvar *soft-heap-limit* nil) +(defvar *soft-heap-limit* + ;; As long as *GC-TRIGGER* is DECLAIMed as INDEX, we know that + ;; MOST-POSITIVE-FIXNUM is a hard limit on how much memory can be + ;; allocated. (Not necessarily *the* hard limit, which is fairly + ;; likely something like a Unix per-process limit that we don't know + ;; about, but a hard limit anyway.) And this gives us a reasonable + ;; conservative default for the soft limit... + (- most-positive-fixnum + *bytes-consed-between-gcs*)) + +;;;; The following specials are used to control when garbage +;;;; collection occurs. ;;; When the dynamic usage increases beyond this amount, the system ;;; notes that a garbage collection needs to occur by setting ;;; *NEED-TO-COLLECT-GARBAGE* to T. It starts out as NIL meaning ;;; nobody has figured out what it should be yet. -(defvar *gc-trigger* nil) - +;;; +;;; FIXME: *GC-TRIGGER* seems to be denominated in bytes, not words. +;;; And limiting it to INDEX is fairly reasonable in order to avoid +;;; bignum arithmetic on every allocation, and to minimize the need +;;; for thought about weird gotchas of the GC-control mechanism itself +;;; consing as it operates. But as of sbcl-0.7.5, 512Mbytes of memory +;;; costs $54.95 at Fry's in Dallas but cheap consumer 64-bit machines +;;; are still over the horizon, so gratuitously limiting our heap size +;;; to FIXNUM bytes seems fairly stupid. It'd be reasonable to +;;; (1) allow arbitrary UNSIGNED-BYTE values of *GC-TRIGGER*, or +;;; (2) redenominate this variable in words instead of bytes, postponing +;;; the problem to heaps which exceed 50% of the machine's address +;;; space, or even +;;; (3) redemoninate this variable in CONS-sized two-word units, +;;; allowing it to cover the entire memory space at the price of +;;; possible loss of clarity. +;;; (And whatever is done, it'd also be good to rename the variable so +;;; that it's clear what unit it's denominated in.) (declaim (type (or index null) *gc-trigger*)) - -;;; On the X86, we store the GC trigger in a ``static'' symbol instead -;;; of letting magic C code handle it. It gets initialized by the -;;; startup code. -#!+x86 -(defvar sb!vm::*internal-gc-trigger*) - -;;;; The following specials are used to control when garbage collection -;;;; occurs. +(defvar *gc-trigger* nil) ;;; When non-NIL, inhibits garbage collection. (defvar *gc-inhibit*) ; initialized in cold init @@ -203,10 +236,11 @@ and submit it as a patch." (defun default-gc-notify-before (notify-stream bytes-in-use) (declare (type stream notify-stream)) - (format notify-stream - "~&; GC is beginning with ~:D bytes in use at internal runtime ~:D.~%" - bytes-in-use - (get-internal-run-time)) + (format + notify-stream + "~&; GC is beginning with ~:D bytes in use at internal runtime ~:D.~%" + bytes-in-use + (get-internal-run-time)) (finish-output notify-stream)) (defparameter *gc-notify-before* #'default-gc-notify-before #!+sb-doc @@ -230,21 +264,21 @@ and submit it as a patch." (finish-output notify-stream)) (defparameter *gc-notify-after* #'default-gc-notify-after #!+sb-doc - "The function bound to this variable is invoked after GC'ing with -the value of *GC-NOTIFY-STREAM*, the amount of dynamic usage (in -bytes) now free, the number of bytes freed by the GC, and the new GC -trigger threshold. The function should notify the user that the system -has finished GC'ing.") + "The function bound to this variable is invoked after GC'ing with the +value of *GC-NOTIFY-STREAM*, the amount of dynamic usage (in bytes) now +free, the number of bytes freed by the GC, and the new GC trigger +threshold; or if *GC-NOTIFY-STREAM* is NIL, it's not invoked. The +function should notify the user that the system has finished GC'ing.") ;;;; internal GC -(sb!alien:def-alien-routine collect-garbage sb!c-call:int - #!+gencgc (last-gen sb!c-call:int)) +(sb!alien:define-alien-routine collect-garbage sb!alien:int + #!+gencgc (last-gen sb!alien:int)) -(sb!alien:def-alien-routine set-auto-gc-trigger sb!c-call:void - (dynamic-usage sb!c-call:unsigned-long)) +(sb!alien:define-alien-routine set-auto-gc-trigger sb!alien:void + (dynamic-usage sb!alien:unsigned-long)) -(sb!alien:def-alien-routine clear-auto-gc-trigger sb!c-call:void) +(sb!alien:define-alien-routine clear-auto-gc-trigger sb!alien:void) ;;; This variable contains the function that does the real GC. This is ;;; for low-level GC experimentation. Do not touch it if you do not @@ -253,7 +287,7 @@ has finished GC'ing.") ;;;; SUB-GC -;;; Used to carefully invoke hooks. +;;; This is used to carefully invoke hooks. (eval-when (:compile-toplevel :execute) (sb!xc:defmacro carefully-funcall (function &rest args) `(handler-case (funcall ,function ,@args) @@ -284,7 +318,7 @@ has finished GC'ing.") *soft-heap-limit*))) (when soft-heap-limit-exceeded? (cerror "Continue with GC." - "soft heap limit exceeded (temporary new limit=~D)" + "soft heap limit exceeded (temporary new limit=~W)" *soft-heap-limit*)) (when (and *gc-trigger* (> pre-gc-dynamic-usage *gc-trigger*)) (setf *need-to-collect-garbage* t))