ligo/vendors/tezos-modded/src/lib_p2p/p2p_maintenance.mli
2019-05-27 11:18:48 +02:00

93 lines
4.1 KiB
OCaml

(*****************************************************************************)
(* *)
(* Open Source License *)
(* Copyright (c) 2018 Dynamic Ledger Solutions, Inc. <contact@tezos.com> *)
(* Copyright (c) 2019 Nomadic Labs, <contact@nomadic-labs.com> *)
(* *)
(* Permission is hereby granted, free of charge, to any person obtaining a *)
(* copy of this software and associated documentation files (the "Software"),*)
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(* Software is furnished to do so, subject to the following conditions: *)
(* *)
(* The above copyright notice and this permission notice shall be included *)
(* in all copies or substantial portions of the Software. *)
(* *)
(* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR*)
(* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, *)
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(* DEALINGS IN THE SOFTWARE. *)
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(*****************************************************************************)
(* min <= min_threshold <= min_target <= max_target <= max_threshold <= max *)
(** P2P maintenance worker.
The P2P layer urges the maintainer to work when the number of
connections reaches `max` or is below `min`. Otherwise, the
maintener is lazy and only looks up for connections every two
minutes (hardcoded constant). The [maintain] function is another
way to signal the maintainer that a maintenance step is desired.
When the maintener detects that the number of connections is over
`max_threshold`, it randomly kills connections to reach
`max_target`.
When the maintener detects that the number of connections is below
`min_threshold`, it creates enough connection to reach at least
`min_target` (and never more than `max_target`). In the process, it
might ask its actual peers for new peers. *)
type bounds = {
min_threshold: int ;
min_target: int ;
max_target: int ;
max_threshold: int ;
}
type config = {
maintenance_idle_time: float ;
(** How long to wait at most, in seconds, before running a maintenance loop. *)
greylist_timeout: int ;
(** GC delay for the greylists tables, in seconds. *)
private_mode: bool ;
(** If [true], only open outgoing/accept incoming connections
to/from peers whose addresses are in [trusted_peers], and inform
these peers that the identity of this node should be revealed to
the rest of the network. *)
}
type 'meta t
(** Type of a maintenance worker. *)
val create:
?discovery:P2p_discovery.t ->
config -> bounds ->
('msg, 'meta, 'meta_conn) P2p_pool.t ->
'meta t
(** [run ?discovery config bounds pool] returns a maintenance worker, with
the [discovery] worker if present, for [pool] with connection targets
specified in [bounds]. *)
val activate: 'meta t -> unit
(** [activate t] start the worker that will maintain connections *)
val maintain: 'meta t -> unit Lwt.t
(** [maintain t] gives a hint to maintenance worker [t] that
maintenance is needed and returns whenever [t] has done a
maintenance cycle. *)
val shutdown: 'meta t -> unit Lwt.t
(** [shutdown t] is a thread that returns whenever [t] has
successfully shut down. *)