Module

The GC module provides an interface to Ruby's mark and sweep garbage collection mechanism.

Some of the underlying methods are also available via the ObjectSpace module.

You may obtain information about the operation of the GC through GC::Profiler.


Constants


internal constants

GC build options

Class Methods


Raises NoMemoryError when allocating an instance of the given classes.

The number of times GC occurred.

It returns the number of times GC occurred since the process started.

Disables garbage collection, returning true if garbage collection was already disabled.

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

Enables garbage collection, returning true if garbage collection was previously disabled.

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

Returns information about the most recent garbage collection.

Returns the size of memory allocated by malloc().

Only available if ruby was built with CALC_EXACT_MALLOC_SIZE.

Returns the number of malloc() allocations.

Only available if ruby was built with CALC_EXACT_MALLOC_SIZE.

No longer raises NoMemoryError when allocating an instance of the given classes.

Initiates garbage collection, unless manually disabled.

This method is defined with keyword arguments that default to true:

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

Use full_mark: false to perform a minor GC. Use immediate_sweep: false to defer sweeping (use lazy sweep).

Note: These keyword arguments are implementation and version dependent. They are not guaranteed to be future-compatible, and may be ignored if the underlying implementation does not support them.

Returns a Hash containing information about the GC.

The hash includes information about internal statistics about GC such as:

{
    :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
}

The contents of the hash are implementation specific and may be changed in the future.

This method is only expected to work on C Ruby.

Returns current status of GC stress mode.

Updates the GC stress mode.

When stress mode is enabled, the GC is invoked at every GC opportunity: all memory and object allocations.

Enabling stress mode will degrade performance, it is only for debugging.

flag can be true, false, or an integer bit-ORed following flags.

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

Verify internal consistency.

This method is implementation specific. Now this method checks generational consistency if RGenGC is supported.

No documentation available

Instance Methods


Initiates garbage collection, unless manually disabled.

This method is defined with keyword arguments that default to true:

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

Use full_mark: false to perform a minor GC. Use immediate_sweep: false to defer sweeping (use lazy sweep).

Note: These keyword arguments are implementation and version dependent. They are not guaranteed to be future-compatible, and may be ignored if the underlying implementation does not support them.