1 /* Copyright (C) 1995,1996,1997,1998,1999,2000,2001, 2002, 2003, 2006,
2 * 2008, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public License
6 * as published by the Free Software Foundation; either version 3 of
7 * the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
20 /* #define DEBUGINFO */
26 #include "libguile/gen-scmconfig.h"
36 extern unsigned long * __libc_ia64_register_backing_store_base
;
39 #include "libguile/_scm.h"
40 #include "libguile/eval.h"
41 #include "libguile/stime.h"
42 #include "libguile/stackchk.h"
43 #include "libguile/struct.h"
44 #include "libguile/smob.h"
45 #include "libguile/arrays.h"
46 #include "libguile/async.h"
47 #include "libguile/ports.h"
48 #include "libguile/root.h"
49 #include "libguile/strings.h"
50 #include "libguile/vectors.h"
51 #include "libguile/hashtab.h"
52 #include "libguile/tags.h"
54 #include "libguile/private-gc.h"
55 #include "libguile/validate.h"
56 #include "libguile/deprecation.h"
57 #include "libguile/gc.h"
58 #include "libguile/dynwind.h"
60 #include "libguile/bdw-gc.h"
62 /* For GC_set_start_callback. */
63 #include <gc/gc_mark.h>
65 #ifdef GUILE_DEBUG_MALLOC
66 #include "libguile/debug-malloc.h"
73 /* Set this to != 0 if every cell that is accessed shall be checked:
75 int scm_debug_cell_accesses_p
= 0;
76 int scm_expensive_debug_cell_accesses_p
= 0;
78 /* Set this to 0 if no additional gc's shall be performed, otherwise set it to
79 * the number of cell accesses after which a gc shall be called.
81 int scm_debug_cells_gc_interval
= 0;
83 /* Hash table that keeps a reference to objects the user wants to protect from
84 garbage collection. */
85 static SCM scm_protects
;
88 #if (SCM_DEBUG_CELL_ACCESSES == 1)
93 Assert that the given object is a valid reference to a valid cell. This
94 test involves to determine whether the object is a cell pointer, whether
95 this pointer actually points into a heap segment and whether the cell
96 pointed to is not a free cell. Further, additional garbage collections may
97 get executed after a user defined number of cell accesses. This helps to
98 find places in the C code where references are dropped for extremely short
103 scm_i_expensive_validation_check (SCM cell
)
105 /* If desired, perform additional garbage collections after a user
106 * defined number of cell accesses.
108 if (scm_debug_cells_gc_interval
)
110 static unsigned int counter
= 0;
118 counter
= scm_debug_cells_gc_interval
;
124 /* Whether cell validation is already running. */
125 static int scm_i_cell_validation_already_running
= 0;
128 scm_assert_cell_valid (SCM cell
)
130 if (!scm_i_cell_validation_already_running
&& scm_debug_cell_accesses_p
)
132 scm_i_cell_validation_already_running
= 1; /* set to avoid recursion */
135 During GC, no user-code should be run, and the guile core
136 should use non-protected accessors.
138 if (scm_gc_running_p
)
142 Only scm_in_heap_p and rescanning the heap is wildly
145 if (scm_expensive_debug_cell_accesses_p
)
146 scm_i_expensive_validation_check (cell
);
148 scm_i_cell_validation_already_running
= 0; /* re-enable */
154 SCM_DEFINE (scm_set_debug_cell_accesses_x
, "set-debug-cell-accesses!", 1, 0, 0,
156 "If @var{flag} is @code{#f}, cell access checking is disabled.\n"
157 "If @var{flag} is @code{#t}, cheap cell access checking is enabled,\n"
158 "but no additional calls to garbage collection are issued.\n"
159 "If @var{flag} is a number, strict cell access checking is enabled,\n"
160 "with an additional garbage collection after the given\n"
161 "number of cell accesses.\n"
162 "This procedure only exists when the compile-time flag\n"
163 "@code{SCM_DEBUG_CELL_ACCESSES} was set to 1.")
164 #define FUNC_NAME s_scm_set_debug_cell_accesses_x
166 if (scm_is_false (flag
))
168 scm_debug_cell_accesses_p
= 0;
170 else if (scm_is_eq (flag
, SCM_BOOL_T
))
172 scm_debug_cells_gc_interval
= 0;
173 scm_debug_cell_accesses_p
= 1;
174 scm_expensive_debug_cell_accesses_p
= 0;
178 scm_debug_cells_gc_interval
= scm_to_signed_integer (flag
, 0, INT_MAX
);
179 scm_debug_cell_accesses_p
= 1;
180 scm_expensive_debug_cell_accesses_p
= 1;
182 return SCM_UNSPECIFIED
;
187 #endif /* SCM_DEBUG_CELL_ACCESSES == 1 */
192 scm_t_c_hook scm_before_gc_c_hook
;
193 scm_t_c_hook scm_before_mark_c_hook
;
194 scm_t_c_hook scm_before_sweep_c_hook
;
195 scm_t_c_hook scm_after_sweep_c_hook
;
196 scm_t_c_hook scm_after_gc_c_hook
;
200 run_before_gc_c_hook (void)
202 if (!SCM_I_CURRENT_THREAD
)
203 /* GC while a thread is spinning up; punt. */
206 scm_c_hook_run (&scm_before_gc_c_hook
, NULL
);
210 /* GC Statistics Keeping
212 unsigned long scm_gc_ports_collected
= 0;
213 static long gc_time_taken
= 0;
214 static long gc_start_time
= 0;
216 static unsigned long free_space_divisor
;
217 static unsigned long minimum_free_space_divisor
;
218 static double target_free_space_divisor
;
220 static unsigned long protected_obj_count
= 0;
223 SCM_SYMBOL (sym_gc_time_taken
, "gc-time-taken");
224 SCM_SYMBOL (sym_heap_size
, "heap-size");
225 SCM_SYMBOL (sym_heap_free_size
, "heap-free-size");
226 SCM_SYMBOL (sym_heap_total_allocated
, "heap-total-allocated");
227 SCM_SYMBOL (sym_heap_allocated_since_gc
, "heap-allocated-since-gc");
228 SCM_SYMBOL (sym_protected_objects
, "protected-objects");
229 SCM_SYMBOL (sym_times
, "gc-times");
232 /* {Scheme Interface to GC}
235 tag_table_to_type_alist (void *closure
, SCM key
, SCM val
, SCM acc
)
237 if (scm_is_integer (key
))
239 int c_tag
= scm_to_int (key
);
241 char const * name
= scm_i_tag_name (c_tag
);
244 key
= scm_from_locale_string (name
);
249 sprintf (s
, "tag %d", c_tag
);
250 key
= scm_from_locale_string (s
);
254 return scm_cons (scm_cons (key
, val
), acc
);
257 SCM_DEFINE (scm_gc_live_object_stats
, "gc-live-object-stats", 0, 0, 0,
259 "Return an alist of statistics of the current live objects. ")
260 #define FUNC_NAME s_scm_gc_live_object_stats
262 SCM tab
= scm_make_hash_table (scm_from_int (57));
266 = scm_internal_hash_fold (&tag_table_to_type_alist
, NULL
, SCM_EOL
, tab
);
272 extern int scm_gc_malloc_yield_percentage
;
273 SCM_DEFINE (scm_gc_stats
, "gc-stats", 0, 0, 0,
275 "Return an association list of statistics about Guile's current\n"
277 #define FUNC_NAME s_scm_gc_stats
280 GC_word heap_size
, free_bytes
, unmapped_bytes
, bytes_since_gc
, total_bytes
;
283 GC_get_heap_usage_safe (&heap_size
, &free_bytes
, &unmapped_bytes
,
284 &bytes_since_gc
, &total_bytes
);
285 gc_times
= GC_get_gc_no ();
288 scm_list_n (scm_cons (sym_gc_time_taken
, scm_from_long (gc_time_taken
)),
289 scm_cons (sym_heap_size
, scm_from_size_t (heap_size
)),
290 scm_cons (sym_heap_free_size
, scm_from_size_t (free_bytes
)),
291 scm_cons (sym_heap_total_allocated
,
292 scm_from_size_t (total_bytes
)),
293 scm_cons (sym_heap_allocated_since_gc
,
294 scm_from_size_t (bytes_since_gc
)),
295 scm_cons (sym_protected_objects
,
296 scm_from_ulong (protected_obj_count
)),
297 scm_cons (sym_times
, scm_from_size_t (gc_times
)),
305 SCM_DEFINE (scm_gc_dump
, "gc-dump", 0, 0, 0,
307 "Dump information about the garbage collector's internal data "
308 "structures and memory usage to the standard output.")
309 #define FUNC_NAME s_scm_gc_dump
313 return SCM_UNSPECIFIED
;
318 SCM_DEFINE (scm_object_address
, "object-address", 1, 0, 0,
320 "Return an integer that for the lifetime of @var{obj} is uniquely\n"
321 "returned by this function for @var{obj}")
322 #define FUNC_NAME s_scm_object_address
324 return scm_from_ulong (SCM_UNPACK (obj
));
329 SCM_DEFINE (scm_gc_disable
, "gc-disable", 0, 0, 0,
331 "Disables the garbage collector. Nested calls are permitted. "
332 "GC is re-enabled once @code{gc-enable} has been called the "
333 "same number of times @code{gc-disable} was called.")
334 #define FUNC_NAME s_scm_gc_disable
337 return SCM_UNSPECIFIED
;
341 SCM_DEFINE (scm_gc_enable
, "gc-enable", 0, 0, 0,
343 "Enables the garbage collector.")
344 #define FUNC_NAME s_scm_gc_enable
347 return SCM_UNSPECIFIED
;
352 SCM_DEFINE (scm_gc
, "gc", 0, 0, 0,
354 "Scans all of SCM objects and reclaims for further use those that are\n"
355 "no longer accessible.")
356 #define FUNC_NAME s_scm_gc
359 /* If you're calling scm_gc(), you probably want synchronous
361 GC_invoke_finalizers ();
362 return SCM_UNSPECIFIED
;
367 scm_i_gc (const char *what
)
374 /* {GC Protection Helper Functions}
379 * If within a function you need to protect one or more scheme objects from
380 * garbage collection, pass them as parameters to one of the
381 * scm_remember_upto_here* functions below. These functions don't do
382 * anything, but since the compiler does not know that they are actually
383 * no-ops, it will generate code that calls these functions with the given
384 * parameters. Therefore, you can be sure that the compiler will keep those
385 * scheme values alive (on the stack or in a register) up to the point where
386 * scm_remember_upto_here* is called. In other words, place the call to
387 * scm_remember_upto_here* _behind_ the last code in your function, that
388 * depends on the scheme object to exist.
390 * Example: We want to make sure that the string object str does not get
391 * garbage collected during the execution of 'some_function' in the code
392 * below, because otherwise the characters belonging to str would be freed and
393 * 'some_function' might access freed memory. To make sure that the compiler
394 * keeps str alive on the stack or in a register such that it is visible to
395 * the conservative gc we add the call to scm_remember_upto_here_1 _after_ the
396 * call to 'some_function'. Note that this would not be necessary if str was
397 * used anyway after the call to 'some_function'.
398 * char *chars = scm_i_string_chars (str);
399 * some_function (chars);
400 * scm_remember_upto_here_1 (str); // str will be alive up to this point.
403 /* Remove any macro versions of these while defining the functions.
404 Functions are always included in the library, for upward binary
405 compatibility and in case combinations of GCC and non-GCC are used. */
406 #undef scm_remember_upto_here_1
407 #undef scm_remember_upto_here_2
410 scm_remember_upto_here_1 (SCM obj SCM_UNUSED
)
412 /* Empty. Protects a single object from garbage collection. */
416 scm_remember_upto_here_2 (SCM obj1 SCM_UNUSED
, SCM obj2 SCM_UNUSED
)
418 /* Empty. Protects two objects from garbage collection. */
422 scm_remember_upto_here (SCM obj SCM_UNUSED
, ...)
424 /* Empty. Protects any number of objects from garbage collection. */
428 These crazy functions prevent garbage collection
429 of arguments after the first argument by
430 ensuring they remain live throughout the
431 function because they are used in the last
432 line of the code block.
433 It'd be better to have a nice compiler hint to
434 aid the conservative stack-scanning GC. --03/09/00 gjb */
436 scm_return_first (SCM elt
, ...)
442 scm_return_first_int (int i
, ...)
449 scm_permanent_object (SCM obj
)
451 return (scm_gc_protect_object (obj
));
455 /* Protect OBJ from the garbage collector. OBJ will not be freed, even if all
456 other references are dropped, until the object is unprotected by calling
457 scm_gc_unprotect_object (OBJ). Calls to scm_gc_protect/unprotect_object nest,
458 i. e. it is possible to protect the same object several times, but it is
459 necessary to unprotect the object the same number of times to actually get
460 the object unprotected. It is an error to unprotect an object more often
461 than it has been protected before. The function scm_protect_object returns
465 /* Implementation note: For every object X, there is a counter which
466 scm_gc_protect_object (X) increments and scm_gc_unprotect_object (X) decrements.
472 scm_gc_protect_object (SCM obj
)
476 /* This critical section barrier will be replaced by a mutex. */
477 /* njrev: Indeed; if my comment above is correct, there is the same
478 critsec/mutex inconsistency here. */
479 SCM_CRITICAL_SECTION_START
;
481 handle
= scm_hashq_create_handle_x (scm_protects
, obj
, scm_from_int (0));
482 SCM_SETCDR (handle
, scm_sum (SCM_CDR (handle
), scm_from_int (1)));
484 protected_obj_count
++;
486 SCM_CRITICAL_SECTION_END
;
492 /* Remove any protection for OBJ established by a prior call to
493 scm_protect_object. This function returns OBJ.
495 See scm_protect_object for more information. */
497 scm_gc_unprotect_object (SCM obj
)
501 /* This critical section barrier will be replaced by a mutex. */
502 /* njrev: and again. */
503 SCM_CRITICAL_SECTION_START
;
505 if (scm_gc_running_p
)
507 fprintf (stderr
, "scm_unprotect_object called during GC.\n");
511 handle
= scm_hashq_get_handle (scm_protects
, obj
);
513 if (scm_is_false (handle
))
515 fprintf (stderr
, "scm_unprotect_object called on unprotected object\n");
520 SCM count
= scm_difference (SCM_CDR (handle
), scm_from_int (1));
521 if (scm_is_eq (count
, scm_from_int (0)))
522 scm_hashq_remove_x (scm_protects
, obj
);
524 SCM_SETCDR (handle
, count
);
526 protected_obj_count
--;
528 SCM_CRITICAL_SECTION_END
;
534 scm_gc_register_root (SCM
*p
)
540 scm_gc_unregister_root (SCM
*p
)
546 scm_gc_register_roots (SCM
*b
, unsigned long n
)
549 for (; p
< b
+ n
; ++p
)
550 scm_gc_register_root (p
);
554 scm_gc_unregister_roots (SCM
*b
, unsigned long n
)
557 for (; p
< b
+ n
; ++p
)
558 scm_gc_unregister_root (p
);
565 MOVE THIS FUNCTION. IT DOES NOT HAVE ANYTHING TODO WITH GC.
568 /* Get an integer from an environment variable. */
570 scm_getenv_int (const char *var
, int def
)
573 char *val
= getenv (var
);
577 res
= strtol (val
, &end
, 10);
584 scm_storage_prehistory ()
586 GC_set_all_interior_pointers (0);
588 free_space_divisor
= scm_getenv_int ("GC_FREE_SPACE_DIVISOR", 3);
589 minimum_free_space_divisor
= free_space_divisor
;
590 target_free_space_divisor
= free_space_divisor
;
591 GC_set_free_space_divisor (free_space_divisor
);
592 GC_set_finalize_on_demand (1);
596 #if (! ((defined GC_VERSION_MAJOR) && (GC_VERSION_MAJOR >= 7))) \
597 && (defined SCM_I_GSC_USE_PTHREAD_THREADS)
598 /* When using GC 6.8, this call is required to initialize thread-local
599 freelists (shouldn't be necessary with GC 7.0). */
603 GC_expand_hp (SCM_DEFAULT_INIT_HEAP_SIZE_2
);
605 /* We only need to register a displacement for those types for which the
606 higher bits of the type tag are used to store a pointer (that is, a
607 pointer to an 8-octet aligned region). For `scm_tc3_struct', this is
608 handled in `scm_alloc_struct ()'. */
609 GC_REGISTER_DISPLACEMENT (scm_tc3_cons
);
610 /* GC_REGISTER_DISPLACEMENT (scm_tc3_unused); */
613 if (!GC_is_visible (&scm_protects
))
616 scm_c_hook_init (&scm_before_gc_c_hook
, 0, SCM_C_HOOK_NORMAL
);
617 scm_c_hook_init (&scm_before_mark_c_hook
, 0, SCM_C_HOOK_NORMAL
);
618 scm_c_hook_init (&scm_before_sweep_c_hook
, 0, SCM_C_HOOK_NORMAL
);
619 scm_c_hook_init (&scm_after_sweep_c_hook
, 0, SCM_C_HOOK_NORMAL
);
620 scm_c_hook_init (&scm_after_gc_c_hook
, 0, SCM_C_HOOK_NORMAL
);
623 scm_i_pthread_mutex_t scm_i_gc_admin_mutex
= SCM_I_PTHREAD_MUTEX_INITIALIZER
;
626 scm_init_gc_protect_object ()
628 scm_protects
= scm_c_make_hash_table (31);
631 /* We can't have a cleanup handler since we have no thread to run it
638 on_exit (cleanup
, 0);
647 SCM scm_after_gc_hook
;
649 static SCM after_gc_async_cell
;
651 /* The function after_gc_async_thunk causes the execution of the
652 * after-gc-hook. It is run after the gc, as soon as the asynchronous
653 * events are handled by the evaluator.
656 after_gc_async_thunk (void)
658 /* Fun, no? Hook-run *and* run-hook? */
659 scm_c_hook_run (&scm_after_gc_c_hook
, NULL
);
660 scm_c_run_hook (scm_after_gc_hook
, SCM_EOL
);
661 return SCM_UNSPECIFIED
;
665 /* The function queue_after_gc_hook is run by the scm_before_gc_c_hook
666 * at the end of the garbage collection. The only purpose of this
667 * function is to mark the after_gc_async (which will eventually lead to
668 * the execution of the after_gc_async_thunk).
671 queue_after_gc_hook (void * hook_data SCM_UNUSED
,
672 void *fn_data SCM_UNUSED
,
673 void *data SCM_UNUSED
)
675 /* If cell access debugging is enabled, the user may choose to perform
676 * additional garbage collections after an arbitrary number of cell
677 * accesses. We don't want the scheme level after-gc-hook to be performed
678 * for each of these garbage collections for the following reason: The
679 * execution of the after-gc-hook causes cell accesses itself. Thus, if the
680 * after-gc-hook was performed with every gc, and if the gc was performed
681 * after a very small number of cell accesses, then the number of cell
682 * accesses during the execution of the after-gc-hook will suffice to cause
683 * the execution of the next gc. Then, guile would keep executing the
684 * after-gc-hook over and over again, and would never come to do other
687 * To overcome this problem, if cell access debugging with additional
688 * garbage collections is enabled, the after-gc-hook is never run by the
689 * garbage collecter. When running guile with cell access debugging and the
690 * execution of the after-gc-hook is desired, then it is necessary to run
691 * the hook explicitly from the user code. This has the effect, that from
692 * the scheme level point of view it seems that garbage collection is
693 * performed with a much lower frequency than it actually is. Obviously,
694 * this will not work for code that depends on a fixed one to one
695 * relationship between the execution counts of the C level garbage
696 * collection hooks and the execution count of the scheme level
700 #if (SCM_DEBUG_CELL_ACCESSES == 1)
701 if (scm_debug_cells_gc_interval
== 0)
704 scm_i_thread
*t
= SCM_I_CURRENT_THREAD
;
706 if (scm_is_false (SCM_CDR (after_gc_async_cell
)))
708 SCM_SETCDR (after_gc_async_cell
, t
->active_asyncs
);
709 t
->active_asyncs
= after_gc_async_cell
;
710 t
->pending_asyncs
= 1;
720 start_gc_timer (void * hook_data SCM_UNUSED
,
721 void *fn_data SCM_UNUSED
,
722 void *data SCM_UNUSED
)
725 gc_start_time
= scm_c_get_internal_run_time ();
731 accumulate_gc_timer (void * hook_data SCM_UNUSED
,
732 void *fn_data SCM_UNUSED
,
733 void *data SCM_UNUSED
)
737 long now
= scm_c_get_internal_run_time ();
738 gc_time_taken
+= now
- gc_start_time
;
745 /* Return some idea of the memory footprint of a process, in bytes.
746 Currently only works on Linux systems. */
748 get_image_size (void)
750 unsigned long size
, resident
, share
;
753 FILE *fp
= fopen ("/proc/self/statm", "r");
755 if (fp
&& fscanf (fp
, "%lu %lu %lu", &size
, &resident
, &share
) == 3)
756 ret
= resident
* 4096;
764 /* These are discussed later. */
765 static size_t bytes_until_gc
;
766 static scm_i_pthread_mutex_t bytes_until_gc_lock
= SCM_I_PTHREAD_MUTEX_INITIALIZER
;
768 /* Make GC run more frequently when the process image size is growing,
769 measured against the number of bytes allocated through the GC.
771 If Guile is allocating at a GC-managed heap size H, libgc will tend
772 to limit the process image size to H*N. But if at the same time the
773 user program is mallocating at a rate M bytes per GC-allocated byte,
774 then the process stabilizes at H*N*M -- assuming that collecting data
775 will result in malloc'd data being freed. It doesn't take a very
776 large M for this to be a bad situation. To limit the image size,
777 Guile should GC more often -- the bigger the M, the more often.
779 Numeric functions that produce bigger and bigger integers are
780 pessimal, because M is an increasing function of time. Here is an
781 example of such a function:
783 (define (factorial n)
787 (fac (1- n) (* n acc))))
790 It is possible for a process to grow for reasons that will not be
791 solved by faster GC. In that case M will be estimated as
792 artificially high for a while, and so GC will happen more often on
793 the Guile side. But when it stabilizes, Guile can ease back the GC
796 The key is to measure process image growth, not mallocation rate.
797 For maximum effectiveness, Guile reacts quickly to process growth,
798 and exponentially backs down when the process stops growing.
800 See http://thread.gmane.org/gmane.lisp.guile.devel/12552/focus=12936
801 for further discussion.
804 adjust_gc_frequency (void * hook_data SCM_UNUSED
,
805 void *fn_data SCM_UNUSED
,
806 void *data SCM_UNUSED
)
808 static size_t prev_image_size
= 0;
809 static size_t prev_bytes_alloced
= 0;
811 size_t bytes_alloced
;
813 scm_i_pthread_mutex_lock (&bytes_until_gc_lock
);
814 bytes_until_gc
= GC_get_heap_size ();
815 scm_i_pthread_mutex_unlock (&bytes_until_gc_lock
);
817 image_size
= get_image_size ();
818 bytes_alloced
= GC_get_total_bytes ();
820 #define HEURISTICS_DEBUG 0
823 fprintf (stderr
, "prev image / alloced: %lu / %lu\n", prev_image_size
, prev_bytes_alloced
);
824 fprintf (stderr
, " image / alloced: %lu / %lu\n", image_size
, bytes_alloced
);
825 fprintf (stderr
, "divisor %lu / %f\n", free_space_divisor
, target_free_space_divisor
);
828 if (prev_image_size
&& bytes_alloced
!= prev_bytes_alloced
)
830 double growth_rate
, new_target_free_space_divisor
;
831 double decay_factor
= 0.5;
832 double hysteresis
= 0.1;
834 growth_rate
= ((double) image_size
- prev_image_size
)
835 / ((double)bytes_alloced
- prev_bytes_alloced
);
838 fprintf (stderr
, "growth rate %f\n", growth_rate
);
841 new_target_free_space_divisor
= minimum_free_space_divisor
;
844 new_target_free_space_divisor
*= 1.0 + growth_rate
;
847 fprintf (stderr
, "new divisor %f\n", new_target_free_space_divisor
);
850 if (new_target_free_space_divisor
< target_free_space_divisor
)
852 target_free_space_divisor
=
853 (decay_factor
* target_free_space_divisor
854 + (1.0 - decay_factor
) * new_target_free_space_divisor
);
857 target_free_space_divisor
= new_target_free_space_divisor
;
860 fprintf (stderr
, "new target divisor %f\n", target_free_space_divisor
);
863 if (free_space_divisor
+ 0.5 + hysteresis
< target_free_space_divisor
864 || free_space_divisor
- 0.5 - hysteresis
> target_free_space_divisor
)
866 free_space_divisor
= lround (target_free_space_divisor
);
868 fprintf (stderr
, "new divisor %lu\n", free_space_divisor
);
870 GC_set_free_space_divisor (free_space_divisor
);
874 prev_image_size
= image_size
;
875 prev_bytes_alloced
= bytes_alloced
;
880 /* The adjust_gc_frequency routine handles transients in the process
881 image size. It can't handle instense non-GC-managed steady-state
882 allocation though, as it decays the FSD at steady-state down to its
885 The only real way to handle continuous, high non-GC allocation is to
886 let the GC know about it. This routine can handle non-GC allocation
887 rates that are similar in size to the GC-managed heap size.
891 scm_gc_register_allocation (size_t size
)
893 scm_i_pthread_mutex_lock (&bytes_until_gc_lock
);
894 if (bytes_until_gc
- size
> bytes_until_gc
)
896 bytes_until_gc
= GC_get_heap_size ();
897 scm_i_pthread_mutex_unlock (&bytes_until_gc_lock
);
902 bytes_until_gc
-= size
;
903 scm_i_pthread_mutex_unlock (&bytes_until_gc_lock
);
911 scm_i_tag_name (scm_t_bits tag
)
913 switch (tag
& 0x7f) /* 7 bits */
917 case scm_tcs_cons_imcar
:
918 return "cons (immediate car)";
919 case scm_tcs_cons_nimcar
:
920 return "cons (non-immediate car)";
921 case scm_tc7_pointer
:
923 case scm_tc7_hashtable
:
925 case scm_tc7_weak_set
:
927 case scm_tc7_weak_table
:
931 case scm_tc7_dynamic_state
:
932 return "dynamic state";
935 case scm_tc7_vm_cont
:
936 return "vm continuation";
938 return "weak vector";
950 case scm_tc16_complex
:
951 return "complex number";
953 case scm_tc16_fraction
:
961 case scm_tc7_stringbuf
:
962 return "string buffer";
967 case scm_tc7_variable
:
975 int k
= 0xff & (tag
>> 8);
976 return (scm_smobs
[k
].name
);
990 /* `GC_INIT ()' was invoked in `scm_storage_prehistory ()'. */
992 scm_after_gc_hook
= scm_make_hook (SCM_INUM0
);
993 scm_c_define ("after-gc-hook", scm_after_gc_hook
);
995 /* When the async is to run, the cdr of the gc_async pair gets set to
996 the asyncs queue of the current thread. */
997 after_gc_async_cell
= scm_cons (scm_c_make_gsubr ("%after-gc-thunk", 0, 0, 0,
998 after_gc_async_thunk
),
1001 scm_c_hook_add (&scm_before_gc_c_hook
, queue_after_gc_hook
, NULL
, 0);
1002 scm_c_hook_add (&scm_before_gc_c_hook
, start_gc_timer
, NULL
, 0);
1003 scm_c_hook_add (&scm_after_gc_c_hook
, accumulate_gc_timer
, NULL
, 0);
1005 /* GC_get_heap_usage does not take a lock, and so can run in the GC
1007 scm_c_hook_add (&scm_before_gc_c_hook
, adjust_gc_frequency
, NULL
, 0);
1009 GC_set_start_callback (run_before_gc_c_hook
);
1011 #include "libguile/gc.x"
1017 #define FUNC_NAME "scm_gc_sweep"
1020 fprintf (stderr
, "%s: doing nothing\n", FUNC_NAME
);