OCaml library : Gc

`sig
type stat = {
minor_words : float;
promoted_words : float;
major_words : float;
minor_collections : int;
major_collections : int;
heap_words : int;
heap_chunks : int;
live_words : int;
live_blocks : int;
free_words : int;
free_blocks : int;
largest_free : int;
fragments : int;
compactions : int;
top_heap_words : int;
stack_size : int;
forced_major_collections : int;
}
type control = {
mutable minor_heap_size : int;
mutable major_heap_increment : int;
mutable space_overhead : int;
mutable verbose : int;
mutable max_overhead : int;
mutable stack_limit : int;
mutable allocation_policy : int;
window_size : int;
custom_major_ratio : int;
custom_minor_ratio : int;
custom_minor_max_size : int;
}
external stat : unit -> Gc.stat = "caml_gc_stat"
external quick_stat : unit -> Gc.stat = "caml_gc_quick_stat"
external counters : unit -> float * float * float = "caml_gc_counters"
external minor_words : unit -> (float [@unboxed]) = "caml_gc_minor_words"
"caml_gc_minor_words_unboxed"
external get : unit -> Gc.control = "caml_gc_get"
external set : Gc.control -> unit = "caml_gc_set"
external minor : unit -> unit = "caml_gc_minor"
external major_slice : int -> int = "caml_gc_major_slice"
external major : unit -> unit = "caml_gc_major"
external full_major : unit -> unit = "caml_gc_full_major"
external compact : unit -> unit = "caml_gc_compaction"
val print_stat : Stdlib.out_channel -> unit
val allocated_bytes : unit -> float
external get_minor_free : unit -> int = "caml_get_minor_free"
external get_bucket : int -> int = "caml_get_major_bucket" [@@noalloc]
external get_credit : unit -> int = "caml_get_major_credit" [@@noalloc]
external huge_fallback_count : unit -> int = "caml_gc_huge_fallback_count"
val finalise : ('a -> unit) -> 'a -> unit
val finalise_last : (unit -> unit) -> 'a -> unit
val finalise_release : unit -> unit
type alarm
val create_alarm : (unit -> unit) -> Gc.alarm
val delete_alarm : Gc.alarm -> unit
external eventlog_pause : unit -> unit = "caml_eventlog_pause"
external eventlog_resume : unit -> unit = "caml_eventlog_resume"
module Memprof :
sig
type allocation_source = Normal | Marshal | Custom
type allocation = private {
n_samples : int;
size : int;
source : Gc.Memprof.allocation_source;
callstack : Stdlib.Printexc.raw_backtrace;
}
type ('minor, 'major) tracker = {
alloc_minor : Gc.Memprof.allocation -> 'minor option;
alloc_major : Gc.Memprof.allocation -> 'major option;
promote : 'minor -> 'major option;
dealloc_minor : 'minor -> unit;
dealloc_major : 'major -> unit;
}
val null_tracker : ('minor, 'major) Gc.Memprof.tracker
val start :
sampling_rate:float ->
?callstack_size:int -> ('minor, 'major) Gc.Memprof.tracker -> unit
val stop : unit -> unit
end
end`