sb!vm:*static-space-free-pointer*))
(eval-when (:compile-toplevel :execute)
- (sb!xc:defmacro def-c-var-frob (lisp-fun c-var-name)
- `(progn
- #!-sb-fluid (declaim (inline ,lisp-fun))
- (defun ,lisp-fun ()
- (sb!alien:extern-alien ,c-var-name (sb!alien:unsigned 32))))))
+ (sb!xc:defmacro def-c-var-fun (lisp-fun c-var-name)
+ `(defun ,lisp-fun ()
+ (sb!alien:extern-alien ,c-var-name (sb!alien:unsigned 32)))))
+#!-sb-fluid
+(declaim (inline current-dynamic-space-start))
+#!+gencgc
+(defun current-dynamic-space-start () sb!vm:dynamic-space-start)
#!-gencgc
-(progn
- ;; This is called once per PROFILEd function call, so it's worth a
- ;; little possible space cost to reduce its time cost.
- #!-sb-fluid
- (declaim (inline current-dynamic-space-start))
- (def-c-var-frob current-dynamic-space-start "current_dynamic_space"))
+(def-c-var-fun current-dynamic-space-start "current_dynamic_space")
#!-sb-fluid
-(declaim (inline dynamic-usage)) ; to reduce PROFILEd call overhead
+(declaim (inline dynamic-usage))
#!+gencgc
-(def-c-var-frob dynamic-usage "bytes_allocated")
+(def-c-var-fun dynamic-usage "bytes_allocated")
#!-gencgc
(defun dynamic-usage ()
(the (unsigned-byte 32)
(defun control-stack-usage ()
#!-stack-grows-downward-not-upward
(- (sb!sys:sap-int (sb!c::control-stack-pointer-sap))
- sb!vm:control-stack-start)
+ (sb!vm:fixnumize sb!vm:*control-stack-start*))
#!+stack-grows-downward-not-upward
- (- sb!vm:control-stack-end
+ (- (sb!vm:fixnumize 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))
- sb!vm:binding-stack-start))
+ (sb!vm:fixnumize sb!vm:*binding-stack-start*)))
\f
;;;; ROOM
(format t "Static space usage is: ~10:D bytes.~%" (static-space-usage))
(format t "Control stack usage is: ~10:D bytes.~%" (control-stack-usage))
(format t "Binding stack usage is: ~10:D bytes.~%" (binding-stack-usage))
+ #!+sb-thread
+ (format t
+ "Control and binding stack usage is for the current thread only.~%")
(format t "Garbage collection is currently ~:[enabled~;DISABLED~].~%"
(> *gc-inhibit* 0)))
:print-summary nil))
(defun room-maximal-info ()
- (room-minimal-info)
- (sb!vm:memory-usage :count-spaces '(:static :dynamic))
- (sb!vm:instance-usage :dynamic :top-n 10)
- (sb!vm:instance-usage :static :top-n 10))
+ ;; FIXME: SB!VM:INSTANCE-USAGE calls suppressed until bug 344 is fixed
+ (room-intermediate-info)
+ ;; old way, could be restored when bug 344 fixed:
+ ;;x (room-minimal-info)
+ ;;x (sb!vm:memory-usage :count-spaces '(:static :dynamic))
+ ;;x (sb!vm:instance-usage :dynamic :top-n 10)
+ ;;x (sb!vm:instance-usage :static :top-n 10)
+ )
(defun room (&optional (verbosity :default))
#!+sb-doc
;;; allocated and never freed.)
(declaim (type unsigned-byte *n-bytes-freed-or-purified*))
(defvar *n-bytes-freed-or-purified* 0)
-(push (lambda ()
- (setf *n-bytes-freed-or-purified* 0))
- ;; KLUDGE: It's probably not quite safely right either to do
- ;; this in *BEFORE-SAVE-INITIALIZATIONS* (since consing, or even
- ;; worse, something which depended on (GET-BYTES-CONSED), might
- ;; happen after that) or in *AFTER-SAVE-INITIALIZATIONS*. But
- ;; it's probably not a big problem, and there seems to be no
- ;; other obvious time to do it. -- WHN 2001-07-30
- *after-save-initializations*)
+(defun gc-reinit ()
+ (gc-on)
+ (gc)
+ (setf *n-bytes-freed-or-purified* 0))
(declaim (ftype (function () unsigned-byte) get-bytes-consed))
(defun get-bytes-consed ()
(+ (dynamic-usage)
*n-bytes-freed-or-purified*))
\f
-;;;; variables and constants
-
-;;; the minimum amount of dynamic space which must be consed before a
-;;; GC will be triggered
-;;;
-;;; 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*
- #!+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
-(defvar *before-gc-hooks* nil ; actually initialized in cold init
- #!+sb-doc
- "A list of functions that are called before garbage collection occurs.
- The functions should take no arguments.")
-
-(defvar *after-gc-hooks* nil ; actually initialized in cold init
- #!+sb-doc
- "A list of functions that are called after garbage collection occurs.
- The functions should take no arguments.")
-
-(defvar *gc-notify-stream* nil ; (actually initialized in cold init)
- #!+sb-doc
- "When non-NIL, this must be a STREAM; and the functions bound to
- *GC-NOTIFY-BEFORE* and *GC-NOTIFY-AFTER* are called with the
- STREAM value before and after a garbage collection occurs
- respectively.")
-
-(defvar *gc-run-time* 0
- #!+sb-doc
- "the total CPU time spent doing garbage collection (as reported by
- GET-INTERNAL-RUN-TIME)")
-(declaim (type index *gc-run-time*))
-
-;;; 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*
- ;; 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*))
+(defvar *after-gc-hooks* nil
+ "Called after each garbage collection. In a multithreaded
+environment these hooks may run in any thread.")
;;;; The following specials are used to control when garbage
;;;; collection occurs.
(declaim (type (or index null) *gc-trigger*))
(defvar *gc-trigger* nil)
-;;; When >0, inhibits garbage collection.
-(defvar *gc-inhibit*) ; initialized in cold init
-
-;;; This flag is used to prevent recursive entry into the garbage
-;;; collector.
-(defvar *already-maybe-gcing*) ; initialized in cold init
-
-;;; When T, indicates that the dynamic usage has exceeded the value
-;;; *GC-TRIGGER*.
+;;; When T, indicates that a GC should have happened but did not due to
+;;; *GC-INHIBIT*.
(defvar *need-to-collect-garbage* nil) ; initialized in cold init
\f
-(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))
- (finish-output notify-stream))
-(defparameter *gc-notify-before* #'default-gc-notify-before
- #!+sb-doc
- "The function bound to this variable is invoked before GC'ing (unless
- *GC-NOTIFY-STREAM* is NIL) with the value of *GC-NOTIFY-STREAM* and
- current amount of dynamic usage (in bytes). It should notify the
- user that the system is going to GC.")
-
-(defun default-gc-notify-after (notify-stream
- bytes-retained
- bytes-freed
- new-trigger)
- (declare (type stream notify-stream))
- (format notify-stream
- "~&; GC has finished with ~:D bytes in use (~:D bytes freed)~@
- ; at internal runtime ~:D. The new GC trigger is ~:D bytes.~%"
- bytes-retained
- bytes-freed
- (get-internal-run-time)
- new-trigger)
- (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; or if *GC-NOTIFY-STREAM* is NIL, it's not invoked. The
-function should notify the user that the system has finished GC'ing.")
-\f
;;;; internal GC
(sb!alien:define-alien-routine collect-garbage sb!alien:int
(#!+gencgc last-gen #!-gencgc ignore sb!alien:int))
-(sb!alien:define-alien-routine set-auto-gc-trigger sb!alien:void
- (dynamic-usage sb!alien:unsigned-long))
-
-(sb!alien:define-alien-routine clear-auto-gc-trigger sb!alien:void)
-
-#!+sb-thread
-(def-c-var-frob gc-thread-pid "gc_thread_pid")
#!+sb-thread
-(defun other-thread-collect-garbage (gen)
- (setf (sb!alien:extern-alien "maybe_gc_pending" (sb!alien:unsigned 32))
- (1+ gen))
- (sb!unix:unix-kill (gc-thread-pid) :SIGALRM))
-
-;;; 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
-;;; know what you are doing.
-(defvar *internal-gc*
- #!+sb-thread #'other-thread-collect-garbage
- #!-sb-thread #'collect-garbage)
-
+(progn
+ (sb!alien:define-alien-routine gc-stop-the-world sb!alien:void)
+ (sb!alien:define-alien-routine gc-start-the-world sb!alien:void))
+#!-sb-thread
+(progn
+ (defun gc-stop-the-world ())
+ (defun gc-start-the-world ()))
+
\f
;;;; SUB-GC
-;;; 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)
- (error (cond)
- (warn "(FUNCALL ~S~{ ~S~}) lost:~%~A" ',function ',args cond)
- nil))))
-
-;;; SUB-GC decides when and if to do a garbage collection. The FORCE-P
-;;; flags controls whether a GC should occur even if the dynamic usage
-;;; is not greater than *GC-TRIGGER*.
+;;; SUB-GC does a garbage collection. This is called from three places:
+;;; (1) The C runtime will call here when it detects that we've consed
+;;; enough to exceed the gc trigger threshold. This is done in
+;;; alloc() for gencgc or interrupt_maybe_gc() for cheneygc
+;;; (2) The user may request a collection using GC, below
+;;; (3) At the end of a WITHOUT-GCING section, we are called if
+;;; *NEED-TO-COLLECT-GARBAGE* is true
;;;
-;;; For GENCGC all generations < GEN will be GC'ed.
+;;; This is different from the behaviour in 0.7 and earlier: it no
+;;; longer decides whether to GC based on thresholds. If you call
+;;; SUB-GC you will definitely get a GC either now or when the
+;;; WITHOUT-GCING is over
-;;; XXX need (1) some kind of locking to ensure that only one thread
-;;; at a time is trying to GC, (2) to look at all these specials and
-;;; work out how much of this "do we really need to GC now?" stuff is
-;;; actually necessary: I think we actually end up GCing every time we
-;;; hit this code
-
-(defun sub-gc (&key force-p (gen 0))
- (/show0 "entering SUB-GC")
- (unless *already-maybe-gcing*
- (let* ((*already-maybe-gcing* t)
- (start-time (get-internal-run-time))
- (pre-gc-dynamic-usage (dynamic-usage))
- ;; Currently we only check *SOFT-HEAP-LIMIT* at GC time,
- ;; not for every allocation. That makes it cheap to do,
- ;; even if it is a little ugly.
- (soft-heap-limit-exceeded? (and *soft-heap-limit*
- (> pre-gc-dynamic-usage
- *soft-heap-limit*)))
- (*soft-heap-limit* (if soft-heap-limit-exceeded?
- (+ pre-gc-dynamic-usage
- *bytes-consed-between-gcs*)
- *soft-heap-limit*)))
- (when soft-heap-limit-exceeded?
- (cerror "Continue with GC."
- "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))
- (when (or force-p
- (and *need-to-collect-garbage* (zerop *gc-inhibit*)))
- ;; KLUDGE: Wow, we really mask interrupts all the time we're
- ;; collecting garbage? That seems like a long time.. -- WHN 19991129
- (without-interrupts
- ;; FIXME: We probably shouldn't do this evil thing to
- ;; *STANDARD-OUTPUT* in a binding which is wrapped around
- ;; calls to user-settable GC hook functions.
- (let ((*standard-output* *terminal-io*))
- (when *gc-notify-stream*
- (if (streamp *gc-notify-stream*)
- (carefully-funcall *gc-notify-before*
- *gc-notify-stream*
- pre-gc-dynamic-usage)
- (warn
- "*GC-NOTIFY-STREAM* is set, but not a STREAM -- ignored.")))
- (dolist (hook *before-gc-hooks*)
- (carefully-funcall hook))
- (when *gc-trigger*
- (clear-auto-gc-trigger))
- (let* (;; We do DYNAMIC-USAGE once more here in order to
- ;; get a more accurate measurement of the space
- ;; actually freed, since the messing around, e.g.
- ;; GC-notify stuff, since the DYNAMIC-USAGE which
- ;; triggered GC could've done a fair amount of
- ;; consing.)
- (pre-internal-gc-dynamic-usage (dynamic-usage))
- (ignore-me (funcall *internal-gc* gen))
- (post-gc-dynamic-usage (dynamic-usage))
- (n-bytes-freed (- pre-internal-gc-dynamic-usage
- post-gc-dynamic-usage))
- ;; In sbcl-0.6.12.39, the raw N-BYTES-FREED from
- ;; GENCGC could sometimes be substantially negative
- ;; (e.g. -5872). I haven't looked into what causes
- ;; that, but I suspect it has to do with
- ;; fluctuating inefficiency in the way that the
- ;; GENCGC packs things into page boundaries.
- ;; Bumping the raw result up to 0 is a little ugly,
- ;; but shouldn't be a problem, and it's even
- ;; possible to sort of justify it: the packing
- ;; inefficiency which has caused (DYNAMIC-USAGE) to
- ;; grow is effectively consing, or at least
- ;; overhead of consing, so it's sort of correct to
- ;; add it to the running total of consing. ("Man
- ;; isn't a rational animal, he's a rationalizing
- ;; animal.":-) -- WHN 2001-06-23
- (eff-n-bytes-freed (max 0 n-bytes-freed)))
- (declare (ignore ignore-me))
- (/show0 "got (DYNAMIC-USAGE) and EFF-N-BYTES-FREED")
- (incf *n-bytes-freed-or-purified*
- eff-n-bytes-freed)
- (/show0 "clearing *NEED-TO-COLLECT-GARBAGE*")
- (setf *need-to-collect-garbage* nil)
- (/show0 "calculating NEW-GC-TRIGGER")
- (let ((new-gc-trigger (+ post-gc-dynamic-usage
- *bytes-consed-between-gcs*)))
- (/show0 "setting *GC-TRIGGER*")
- (setf *gc-trigger* new-gc-trigger))
- (/show0 "calling SET-AUTO-GC-TRIGGER")
- (set-auto-gc-trigger *gc-trigger*)
- (dolist (hook *after-gc-hooks*)
- (/show0 "doing a hook from *AFTER-GC--HOOKS*")
- ;; FIXME: This hook should be called with the same
- ;; kind of information as *GC-NOTIFY-AFTER*. In
- ;; particular, it would be nice for the hook function
- ;; to be able to adjust *GC-TRIGGER* intelligently to
- ;; e.g. 108% of total memory usage.
- (carefully-funcall hook))
- (when *gc-notify-stream*
- (if (streamp *gc-notify-stream*)
- (carefully-funcall *gc-notify-after*
- *gc-notify-stream*
- post-gc-dynamic-usage
- eff-n-bytes-freed
- *gc-trigger*)
- (warn
- "*GC-NOTIFY-STREAM* is set, but not a stream -- ignored.")))))
- (scrub-control-stack))) ;XXX again? we did this from C ...
- (incf *gc-run-time* (- (get-internal-run-time)
- start-time))))
- ;; FIXME: should probably return (VALUES), here and in RETURN-FROM
- nil)
+;;; For GENCGC all generations < GEN will be GC'ed.
-;;; This routine is called by the allocation miscops to decide whether
-;;; a GC should occur. The argument, OBJECT, is the newly allocated
-;;; object which must be returned to the caller.
-(defun maybe-gc (&optional object)
- (sub-gc)
- object)
+(defvar *already-in-gc*
+ (sb!thread:make-mutex :name "GC lock") "ID of thread running SUB-GC")
+
+(defun sub-gc (&key (gen 0))
+ (unless (eql (sb!thread:current-thread-id)
+ (sb!thread::mutex-value *already-in-gc*))
+ ;; With gencgc, unless *NEED-TO-COLLECT-GARBAGE* every allocation
+ ;; in this function triggers another gc, potentially exceeding
+ ;; maximum interrupt nesting.
+ (setf *need-to-collect-garbage* t)
+ (when (zerop *gc-inhibit*)
+ (sb!thread:with-mutex (*already-in-gc*)
+ (let ((old-usage (dynamic-usage))
+ (new-usage 0))
+ (unsafe-clear-roots)
+ ;; We need to disable interrupts for GC, but we also want
+ ;; to run as little as possible without them.
+ (without-interrupts
+ (gc-stop-the-world)
+ (collect-garbage gen)
+ (setf *need-to-collect-garbage* nil
+ new-usage (dynamic-usage))
+ (gc-start-the-world))
+ ;; Interrupts re-enabled, but still inside the mutex.
+ ;; In a multithreaded environment the other threads will
+ ;; see *n-b-f-o-p* change a little late, but that's OK.
+ (let ((freed (- old-usage new-usage)))
+ ;; GENCGC occasionally reports negative here, but the
+ ;; current belief is that it is part of the normal order
+ ;; of things and not a bug.
+ (when (plusp freed)
+ (incf *n-bytes-freed-or-purified* freed)))
+ (sb!thread::reap-dead-threads)))
+ ;; Outside the mutex, these may cause another GC. FIXME: it can
+ ;; potentially exceed maximum interrupt nesting by triggering
+ ;; GCs.
+ (run-pending-finalizers)
+ (dolist (hook *after-gc-hooks*)
+ (handler-case
+ (funcall hook)
+ (error (c)
+ (warn "Error calling after GC hook ~S:~% ~S" hook c)))))))
;;; This is the user-advertised garbage collection function.
(defun gc (&key (gen 0) (full nil) &allow-other-keys)
#!+(and sb-doc (not gencgc))
"Initiate a garbage collection. GEN may be provided for compatibility with
generational garbage collectors, but is ignored in this implementation."
- (sub-gc :force-p t :gen (if full 6 gen)))
+ (sub-gc :gen (if full 6 gen)))
+
+(defun unsafe-clear-roots ()
+ ;; KLUDGE: Do things in an attempt to get rid of extra roots. Unsafe
+ ;; as having these cons more then we have space left leads to huge
+ ;; badness.
+ (scrub-control-stack)
+ ;; FIXME: CTYPE-OF-CACHE-CLEAR isn't thread-safe.
+ #!-sb-thread
+ (ctype-of-cache-clear))
\f
;;;; auxiliary functions
#!+sb-doc
"Return the amount of memory that will be allocated before the next garbage
collection is initiated. This can be set with SETF."
- *bytes-consed-between-gcs*)
+ (sb!alien:extern-alien "bytes_consed_between_gcs"
+ (sb!alien:unsigned 32)))
+
(defun (setf bytes-consed-between-gcs) (val)
- ;; FIXME: Shouldn't this (and the DECLAIM for the underlying variable)
- ;; be for a strictly positive number type, e.g.
- ;; (AND (INTEGER 1) FIXNUM)?
(declare (type index val))
- (let ((old *bytes-consed-between-gcs*))
- (setf *bytes-consed-between-gcs* val)
- (when *gc-trigger*
- (setf *gc-trigger* (+ *gc-trigger* (- val old)))
- (cond ((<= (dynamic-usage) *gc-trigger*)
- (clear-auto-gc-trigger)
- (set-auto-gc-trigger *gc-trigger*))
- (t
- ;; FIXME: If SCRUB-CONTROL-STACK is required here, why
- ;; isn't it built into SUB-GC? And *is* it required here?
- (sb!sys:scrub-control-stack)
- (sub-gc)))))
- val)
+ (setf (sb!alien:extern-alien "bytes_consed_between_gcs"
+ (sb!alien:unsigned 32))
+ val))
+;;; FIXME: Aren't these utterly wrong if called inside WITHOUT-GCING?
+;;; Unless something that works there too can be deviced this fact
+;;; should be documented.
(defun gc-on ()
#!+sb-doc
"Enable the garbage collector."
"Disable the garbage collector."
(setq *gc-inhibit* 1)
nil)
-\f
-;;;; initialization stuff
-(defun gc-reinit ()
- (when *gc-trigger*
- (if (< *gc-trigger* (dynamic-usage))
- (sub-gc)
- (set-auto-gc-trigger *gc-trigger*))))