Module 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;
How much to add to the major heap when increasing it. If this number is less than or equal to 1000, it is a percentage of the current heap size (i.e. setting it to 100 will double the heap size at each increase). If it is more than 1000, it is a fixed number of words that will be added to the heap.
Default: 15%.
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. Ifmax_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). Ifmax_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
custom_major_ratio : Core_kernel__.Import.int;
Target ratio of floating garbage to major heap size for out-of-heap memory held by custom values located in the major heap. The GC speed is adjusted to try to use this much memory for dead values that are not yet collected. Expressed as a percentage of major heap size. The default value keeps the out-of-heap floating garbage about the same size as the in-heap overhead. Note: this only applies to values allocated with
caml_alloc_custom_mem
(e.g. bigarrays). Default: 44.- since
- 4.08.0
custom_minor_ratio : Core_kernel__.Import.int;
Bound on floating garbage for out-of-heap memory held by custom values in the minor heap. A minor GC is triggered when this much memory is held by custom values located in the minor heap. Expressed as a percentage of minor heap size. Note: this only applies to values allocated with
caml_alloc_custom_mem
(e.g. bigarrays). Default: 100.- since
- 4.08.0
custom_minor_max_size : Core_kernel__.Import.int;
Maximum amount of out-of-heap memory for each custom value allocated in the minor heap. When a custom value is allocated on the minor heap and holds more than this many bytes, only this value is counted against
custom_minor_ratio
and the rest is directly counted againstcustom_major_ratio
. Note: this only applies to values allocated withcaml_alloc_custom_mem
(e.g. bigarrays). Default: 8192 bytes.- since
- 4.08.0
}
include Bin_prot.Binable.S with type t := t
include Bin_prot.Binable.S_only_functions with type t := t
val bin_size_t : t Bin_prot.Size.sizer
val bin_write_t : t Bin_prot.Write.writer
val bin_read_t : t Bin_prot.Read.reader
val __bin_read_t__ : (int -> t) Bin_prot.Read.reader
This function only needs implementation if
t
exposed to be a polymorphic variant. Despite what the type reads, this does *not* produce a function after reading; instead it takes the constructor tag (int) before reading and reads the rest of the variantt
afterwards.
val bin_shape_t : Bin_prot.Shape.t
val bin_writer_t : t Bin_prot.Type_class.writer
val bin_reader_t : t Bin_prot.Type_class.reader
val bin_t : t Bin_prot.Type_class.t
include Ppx_sexp_conv_lib.Sexpable.S with type t := t
val t_of_sexp : Sexplib0.Sexp.t -> t
val sexp_of_t : t -> Sexplib0.Sexp.t
val custom_minor_max_size : t -> Core_kernel__.Import.int
val custom_minor_ratio : t -> Core_kernel__.Import.int
val custom_major_ratio : t -> Core_kernel__.Import.int
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 set_verbose : t -> Core_kernel__.Import.int -> Core_kernel__.Import.unit
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
val ascending : t -> t -> int
ascending
is identical tocompare
.descending x y = ascending y x
. These are intended to be mnemonic when used likeList.sort ~compare:ascending
andList.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
meanslow <= t <= high
val clamp_exn : t -> min:t -> max:t -> t
clamp_exn t ~min ~max
returnst'
, the closest value tot
such thatbetween 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
val comparator : (t, comparator_witness) Base.Comparator.comparator
include Base__.Comparable_intf.Validate with type t := 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 Replace_polymorphic_compare : Core_kernel__.Comparable_intf.Polymorphic_compare with type t := t
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