GC

module GC

GC模块为Ruby的标记和清理垃圾收集机制提供了一个接口。

一些底层方法也可以通过ObjectSpace模块获得。

您可以通过GC::Profiler获取有关GC操作的信息。

常量

INTERNAL_CONSTANTS OPTS

Public Class Methods

add_stress_to_class(*args) Show source

static VALUE
rb_gcdebug_add_stress_to_class(int argc, VALUE *argv, VALUE self)
{
    rb_objspace_t *objspace = &rb_objspace;

    if (!stress_to_class) {
        stress_to_class = rb_ary_tmp_new(argc
    }
    rb_ary_cat(stress_to_class, argv, argc
    return self;
}

count → Integer Show source

GC发生的次数。

它返回自进程启动以来GC发生的次数。

static VALUE
gc_count(VALUE self)
{
    return SIZET2NUM(rb_gc_count()
}

disable → true or false Show source

禁用垃圾收集，如果垃圾收集已被禁用则返回true。

GC.disable   #=> false
GC.disable   #=> true

VALUE
rb_gc_disable(void)
{
    rb_objspace_t *objspace = &rb_objspace;
    int old = dont_gc;

    gc_rest(objspace

    dont_gc = TRUE;
    return old ? Qtrue : Qfalse;
}

enable → true or false Show source

启用垃圾回收，如果先前禁用垃圾回收，则返回true。

GC.disable   #=> false
GC.enable    #=> true
GC.enable    #=> false

VALUE
rb_gc_enable(void)
{
    rb_objspace_t *objspace = &rb_objspace;
    int old = dont_gc;

    dont_gc = FALSE;
    return old ? Qtrue : Qfalse;
}

latest_gc_info -> {:gc_by→:newobj} Show source

latest_gc_info(hash) → hash

latest_gc_info(:major_by) → :malloc

返回有关最新垃圾回收的信息。

static VALUE
gc_latest_gc_info(int argc, VALUE *argv, VALUE self)
{
    rb_objspace_t *objspace = &rb_objspace;
    VALUE arg = Qnil;

    if (rb_scan_args(argc, argv, "01", &arg) == 1) {
        if (!SYMBOL_P(arg) && !RB_TYPE_P(arg, T_HASH)) {
            rb_raise(rb_eTypeError, "non-hash or symbol given"
        }
    }

    if (arg == Qnil) {
        arg = rb_hash_new(
    }

    return gc_info_decode(objspace, arg, 0
}

malloc_allocated_size → Integer Show source

返回由malloc()分配的内存大小。

只有在使用ruby构建时才可用CALC_EXACT_MALLOC_SIZE。

static VALUE
gc_malloc_allocated_size(VALUE self)
{
    return UINT2NUM(rb_objspace.malloc_params.allocated_size
}

malloc_allocations → Integer Show source

返回malloc()分配的数量。

只有在使用ruby构建时才可用CALC_EXACT_MALLOC_SIZE。

static VALUE
gc_malloc_allocations(VALUE self)
{
    return UINT2NUM(rb_objspace.malloc_params.allocations
}

remove_stress_to_class(*args) Show source

static VALUE
rb_gcdebug_remove_stress_to_class(int argc, VALUE *argv, VALUE self)
{
    rb_objspace_t *objspace = &rb_objspace;
    int i;

    if (stress_to_class) {
        for (i = 0; i < argc; ++i) {
            rb_ary_delete_same(stress_to_class, argv[i]
        }
        if (RARRAY_LEN(stress_to_class) == 0) {
            stress_to_class = 0;
        }
    }
    return Qnil;
}

start → nil Show source

start(full_mark: true, immediate_sweep: true) → nil

启动垃圾回收，除非手动禁用。

该方法使用默认为true的关键字参数进行定义：

def GC.start(full_mark: true, immediate_sweep: true end

使用full_mark：false来执行次要GC。使用immediate_sweep：false推迟清理（使用懒惰扫描）。

注意：这些关键字参数是实现和版本相关的。它们不保证与未来兼容，如果底层实现不支持它们，可能会被忽略。

static VALUE
gc_start_internal(int argc, VALUE *argv, VALUE self)
{
    rb_objspace_t *objspace = &rb_objspace;
    int full_mark = TRUE, immediate_mark = TRUE, immediate_sweep = TRUE;
    VALUE opt = Qnil;
    static ID keyword_ids[3];

    rb_scan_args(argc, argv, "0:", &opt

    if (!NIL_P(opt)) {
        VALUE kwvals[3];

        if (!keyword_ids[0]) {
            keyword_ids[0] = rb_intern("full_mark"
            keyword_ids[1] = rb_intern("immediate_mark"
            keyword_ids[2] = rb_intern("immediate_sweep"
        }

        rb_get_kwargs(opt, keyword_ids, 0, 3, kwvals

        if (kwvals[0] != Qundef) full_mark = RTEST(kwvals[0]
        if (kwvals[1] != Qundef) immediate_mark = RTEST(kwvals[1]
        if (kwvals[2] != Qundef) immediate_sweep = RTEST(kwvals[2]
    }

    garbage_collect(objspace, full_mark, immediate_mark, immediate_sweep, GPR_FLAG_METHOD
    gc_finalize_deferred(objspace

    return Qnil;
}

stat → Hash Show source

stat(hash) → hash

stat(:key) → Numeric

返回包含有关GC的信息的哈希。

哈希包含有关GC的内部统计信息，例如：

{
    :count=>0,
    :heap_allocated_pages=>24,
    :heap_sorted_length=>24,
    :heap_allocatable_pages=>0,
    :heap_available_slots=>9783,
    :heap_live_slots=>7713,
    :heap_free_slots=>2070,
    :heap_final_slots=>0,
    :heap_marked_slots=>0,
    :heap_eden_pages=>24,
    :heap_tomb_pages=>0,
    :total_allocated_pages=>24,
    :total_freed_pages=>0,
    :total_allocated_objects=>7796,
    :total_freed_objects=>83,
    :malloc_increase_bytes=>2389312,
    :malloc_increase_bytes_limit=>16777216,
    :minor_gc_count=>0,
    :major_gc_count=>0,
    :remembered_wb_unprotected_objects=>0,
    :remembered_wb_unprotected_objects_limit=>0,
    :old_objects=>0,
    :old_objects_limit=>0,
    :oldmalloc_increase_bytes=>2389760,
    :oldmalloc_increase_bytes_limit=>16777216
}

散列的内容是特定于实现的，将来可能会更改。

此方法仅适用于C Ruby。

static VALUE
gc_stat(int argc, VALUE *argv, VALUE self)
{
    VALUE arg = Qnil;

    if (rb_scan_args(argc, argv, "01", &arg) == 1) {
        if (SYMBOL_P(arg)) {
            size_t value = gc_stat_internal(arg
            return SIZET2NUM(value
        }
        else if (!RB_TYPE_P(arg, T_HASH)) {
            rb_raise(rb_eTypeError, "non-hash or symbol given"
        }
    }

    if (arg == Qnil) {
        arg = rb_hash_new(
    }
    gc_stat_internal(arg
    return arg;
}

stress → integer, true or false Show source

返回GC应力模式的当前状态。

static VALUE
gc_stress_get(VALUE self)
{
    rb_objspace_t *objspace = &rb_objspace;
    return ruby_gc_stress_mode;
}

stress = flag → flag Show source

Updates the GC stress mode.

当启用压力模式时，GC会在每个GC机会中调用：所有内存和对象分配。

启用压力模式会降低性能，仅用于调试。

标志可以是true，false，或者是一个整型位或符号后面的标志。

0x01:: no major GC
0x02:: no immediate sweep
0x04:: full mark after malloc/calloc/realloc

static VALUE
gc_stress_set_m(VALUE self, VALUE flag)
{
    rb_objspace_t *objspace = &rb_objspace;
    gc_stress_set(objspace, flag
    return flag;
}

verify_internal_consistency → nil Show source

验证内部一致性。

该方法是特定于实现的。现在，如果支持RGenGC，此方法将检查代数一致性。

static VALUE
gc_verify_internal_consistency(VALUE dummy)
{
    rb_objspace_t *objspace = &rb_objspace;
    struct verify_internal_consistency_struct data = {0};
    struct each_obj_args eo_args;

    data.objspace = objspace;
    gc_report(5, objspace, "gc_verify_internal_consistency: start\n"

    /* check relations */

    eo_args.callback = verify_internal_consistency_i;
    eo_args.data = (void *)&data;
    objspace_each_objects((VALUE)&eo_args

    if (data.err_count != 0) {
#if RGENGC_CHECK_MODE >= 5
        objspace->rgengc.error_count = data.err_count;
        gc_marks_check(objspace, NULL, NULL
        allrefs_dump(objspace
#endif
        rb_bug("gc_verify_internal_consistency: found internal inconsistency."
    }

    /* check heap_page status */
    gc_verify_heap_pages(objspace

    /* check counters */

    if (!is_lazy_sweeping(heap_eden) && !finalizing) {
        if (objspace_live_slots(objspace) != data.live_object_count) {
            fprintf(stderr, "heap_pages_final_slots: %d, objspace->profile.total_freed_objects: %d\n",
                    (int)heap_pages_final_slots, (int)objspace->profile.total_freed_objects
            rb_bug("inconsistent live slot nubmer: expect %"PRIuSIZE", but %"PRIuSIZE".", objspace_live_slots(objspace), data.live_object_count
        }
    }

#if USE_RGENGC
    if (!is_marking(objspace)) {
        if (objspace->rgengc.old_objects != data.old_object_count) {
            rb_bug("inconsistent old slot nubmer: expect %"PRIuSIZE", but %"PRIuSIZE".", objspace->rgengc.old_objects, data.old_object_count
        }
        if (objspace->rgengc.uncollectible_wb_unprotected_objects != data.remembered_shady_count) {
            rb_bug("inconsistent old slot nubmer: expect %"PRIuSIZE", but %"PRIuSIZE".", objspace->rgengc.uncollectible_wb_unprotected_objects, data.remembered_shady_count
        }
    }
#endif

    if (!finalizing) {
        size_t list_count = 0;

        {
            VALUE z = heap_pages_deferred_final;
            while (z) {
                list_count++;
                z = RZOMBIE(z)->next;
            }
        }

        if (heap_pages_final_slots != data.zombie_object_count ||
            heap_pages_final_slots != list_count) {

            rb_bug("inconsistent finalizing object count:\n"
                   "  expect %"PRIuSIZE"\n"
                   "  but    %"PRIuSIZE" zombies\n"
                   "  heap_pages_deferred_final list has %"PRIuSIZE" items.",
                   heap_pages_final_slots,
                   data.zombie_object_count,
                   list_count
        }
    }

    gc_report(5, objspace, "gc_verify_internal_consistency: OK\n"

    return Qnil;
}

Public Instance Methods

garbage_collect → nil Show source

include GC; garbage_collect → nil

garbage_collect(full_mark: true, immediate_sweep: true) → nil

启动垃圾回收，除非手动禁用。

该方法使用默认为true的关键字参数进行定义：

def GC.start(full_mark: true, immediate_sweep: true end

使用full_mark：false来执行次要GC。使用immediate_sweep：false推迟清理（使用懒惰扫描）。

注意：这些关键字参数是实现和版本相关的。它们不保证与未来兼容，如果底层实现不支持它们，可能会被忽略。

static VALUE
gc_start_internal(int argc, VALUE *argv, VALUE self)
{
    rb_objspace_t *objspace = &rb_objspace;
    int full_mark = TRUE, immediate_mark = TRUE, immediate_sweep = TRUE;
    VALUE opt = Qnil;
    static ID keyword_ids[3];

    rb_scan_args(argc, argv, "0:", &opt

    if (!NIL_P(opt)) {
        VALUE kwvals[3];

        if (!keyword_ids[0]) {
            keyword_ids[0] = rb_intern("full_mark"
            keyword_ids[1] = rb_intern("immediate_mark"
            keyword_ids[2] = rb_intern("immediate_sweep"
        }

        rb_get_kwargs(opt, keyword_ids, 0, 3, kwvals

        if (kwvals[0] != Qundef) full_mark = RTEST(kwvals[0]
        if (kwvals[1] != Qundef) immediate_mark = RTEST(kwvals[1]
        if (kwvals[2] != Qundef) immediate_sweep = RTEST(kwvals[2]
    }

    garbage_collect(objspace, full_mark, immediate_mark, immediate_sweep, GPR_FLAG_METHOD
    gc_finalize_deferred(objspace

    return Qnil;
}