Module Core_kernel.Gc.Control

type t = {
mutable minor_heap_size : Core_kernel__.Import.int;

(** The size (in words) of the minor heap. Changing this parameter will trigger a minor collection.

Default: 262144 words / 1MB (32bit) / 2MB (64bit). *)

mutable major_heap_increment : Core_kernel__.Import.int;

(** The minimum number of words to add to the major heap when increasing it.

Default: 126976 words / 0.5MB (32bit) / 1MB (64bit). *)

mutable space_overhead : Core_kernel__.Import.int;

(** The major GC speed is computed from this parameter. This is the memory that will be "wasted" because the GC does not immediatly collect unreachable blocks. It is expressed as a percentage of the memory used for live data. The GC will work more (use more CPU time and collect blocks more eagerly) if space_overhead is smaller.

Default: 80. *)

mutable verbose : Core_kernel__.Import.int;

(** This value controls the GC messages on standard error output. It is a sum of some of the following flags, to print messages on the corresponding events:

  • 0x001 Start of major GC cycle.
  • 0x002 Minor collection and major GC slice.
  • 0x004 Growing and shrinking of the heap.
  • 0x008 Resizing of stacks and memory manager tables.
  • 0x010 Heap compaction.
  • 0x020 Change of GC parameters.
  • 0x040 Computation of major GC slice size.
  • 0x080 Calling of finalisation functions.
  • 0x100 Bytecode executable search at start-up.
  • 0x200 Computation of compaction triggering condition.

Default: 0. *)

mutable max_overhead : Core_kernel__.Import.int;

(** Heap compaction is triggered when the estimated amount of "wasted" memory is more than max_overhead percent of the amount of live data. If max_overhead is set to 0, heap compaction is triggered at the end of each major GC cycle (this setting is intended for testing purposes only). If max_overhead >= 1000000, compaction is never triggered.

Default: 500. *)

mutable stack_limit : Core_kernel__.Import.int;

(** The maximum size of the stack (in words). This is only relevant to the byte-code runtime, as the native code runtime uses the operating system's stack.

Default: 1048576 words / 4MB (32bit) / 8MB (64bit). *)

mutable allocation_policy : Core_kernel__.Import.int;

(** The policy used for allocating in the heap. Possible values are 0 and 1. 0 is the next-fit policy, which is quite fast but can result in fragmentation. 1 is the first-fit policy, which can be slower in some cases but can be better for programs with fragmentation problems.

Default: 0. *)

window_size : Core_kernel__.Import.int;

(** The size of the window used by the major GC for smoothing out variations in its workload. This is an integer between 1 and 50.

Default: 1.

  • Since: 4.03.0

*)

}
include sig ... end
val bin_read_t : t Bin_prot.Read.reader
val __bin_read_t__ : (Core_kernel__.Import.int ‑> t) Bin_prot.Read.reader
val bin_reader_t : t Bin_prot.Type_class.reader
val bin_size_t : t Bin_prot.Size.sizer
val bin_write_t : t Bin_prot.Write.writer
val bin_writer_t : t Bin_prot.Type_class.writer
val bin_shape_t : Bin_prot.Shape.t
val t_of_sexp : Base.Sexp.t ‑> t
val sexp_of_t : t ‑> Base.Sexp.t
val window_size : t ‑> Core_kernel__.Import.int
val allocation_policy : t ‑> Core_kernel__.Import.int
val set_allocation_policy : t ‑> Core_kernel__.Import.int ‑> Core_kernel__.Import.unit
val stack_limit : t ‑> Core_kernel__.Import.int
val set_stack_limit : t ‑> Core_kernel__.Import.int ‑> Core_kernel__.Import.unit
val max_overhead : t ‑> Core_kernel__.Import.int
val set_max_overhead : t ‑> Core_kernel__.Import.int ‑> Core_kernel__.Import.unit
val verbose : t ‑> Core_kernel__.Import.int
val space_overhead : t ‑> Core_kernel__.Import.int
val set_space_overhead : t ‑> Core_kernel__.Import.int ‑> Core_kernel__.Import.unit
val major_heap_increment : t ‑> Core_kernel__.Import.int
val set_major_heap_increment : t ‑> Core_kernel__.Import.int ‑> Core_kernel__.Import.unit
val minor_heap_size : t ‑> Core_kernel__.Import.int
val set_minor_heap_size : t ‑> Core_kernel__.Import.int ‑> Core_kernel__.Import.unit
module Fields : sig ... end
include Comparable.S with type t := t
include Core_kernel__.Comparable_intf.S_common
include Base.Comparable.S
include Base__.Comparable_intf.Polymorphic_compare
include Base.Comparisons.Infix
type t
val (>=) : t ‑> t ‑> bool
val (<=) : t ‑> t ‑> bool
val (=) : t ‑> t ‑> bool
val (>) : t ‑> t ‑> bool
val (<) : t ‑> t ‑> bool
val (<>) : t ‑> t ‑> bool
val equal : t ‑> t ‑> bool
val compare : t ‑> t ‑> int

compare t1 t2 returns 0 if t1 is equal to t2, a negative integer if t1 is less than t2, and a positive integer if t1 is greater than t2.

val min : t ‑> t ‑> t
val max : t ‑> t ‑> t
val ascending : t ‑> t ‑> int

ascending is identical to compare. descending x y = ascending y x. These are intended to be mnemonic when used like List.sort ~compare:ascending and List.sort ~cmp:descending, since they cause the list to be sorted in ascending or descending order, respectively.

val descending : t ‑> t ‑> int
val between : t ‑> low:t ‑> high:t ‑> bool

between t ~low ~high means low <= t <= high

val clamp_exn : t ‑> min:t ‑> max:t ‑> t

clamp_exn t ~min ~max returns t', the closest value to t such that between t' ~low:min ~high:max is true.

Raises if not (min <= max).

val clamp : t ‑> min:t ‑> max:t ‑> t Base.Or_error.t
include Base.Comparator.S with type t := t
type t
type comparator_witness
include Base__.Comparable_intf.Validate with type t := t
type t
val validate_lbound : min:t Base.Maybe_bound.t ‑> t Base.Validate.check
val validate_ubound : max:t Base.Maybe_bound.t ‑> t Base.Validate.check
val validate_bound : min:t Base.Maybe_bound.t ‑> max:t Base.Maybe_bound.t ‑> t Base.Validate.check
module Map : Map.S with type Key.t = t with type Key.comparator_witness = comparator_witness
module Set : Set.S with type Elt.t = t with type Elt.comparator_witness = comparator_witness