Files
transmission/libtransmission/peer-mgr-wishlist.h
Yat Ho 2a3a8ea364 perf: even faster wishlist (#7744)
* chore: add comments to annotate observer dependencies

* refactor: overhaul wishlist

Avoid expensive `count_active_requests` and `has_active_request_to_peer`.
- Remove "endgame"
- Never rebuild candidate list mid-download

* chore: code cleanup

* test: fix

* perf: sort block list in reverse order

* refactor: reduce request timeout from 90 to 15 seconds
2025-11-02 11:55:38 -06:00

85 lines
4.2 KiB
C++

// This file Copyright © Mnemosyne LLC.
// It may be used under GPLv2 (SPDX: GPL-2.0-only), GPLv3 (SPDX: GPL-3.0-only),
// or any future license endorsed by Mnemosyne LLC.
// License text can be found in the licenses/ folder.
#pragma once
#ifndef LIBTRANSMISSION_PEER_MODULE
#error only the libtransmission peer module should #include this header.
#endif
#include <cstddef> // size_t
#include <functional>
#include <memory>
#include <vector>
#include "libtransmission/transmission.h"
#include "libtransmission/observable.h"
#include "libtransmission/utils.h"
class tr_bitfield;
struct tr_peer;
/**
* Figures out what blocks we want to request next.
*/
class Wishlist
{
public:
struct Mediator
{
[[nodiscard]] virtual bool client_has_block(tr_block_index_t block) const = 0;
[[nodiscard]] virtual bool client_has_piece(tr_piece_index_t piece) const = 0;
[[nodiscard]] virtual bool client_wants_piece(tr_piece_index_t piece) const = 0;
[[nodiscard]] virtual bool is_sequential_download() const = 0;
[[nodiscard]] virtual size_t count_piece_replication(tr_piece_index_t piece) const = 0;
[[nodiscard]] virtual tr_block_span_t block_span(tr_piece_index_t piece) const = 0;
[[nodiscard]] virtual tr_piece_index_t piece_count() const = 0;
[[nodiscard]] virtual tr_priority_t priority(tr_piece_index_t piece) const = 0;
[[nodiscard]] virtual libtransmission::ObserverTag observe_files_wanted_changed(
libtransmission::SimpleObservable<tr_torrent*, tr_file_index_t const*, tr_file_index_t, bool>::Observer) = 0;
[[nodiscard]] virtual libtransmission::ObserverTag observe_peer_disconnect(
libtransmission::SimpleObservable<tr_torrent*, tr_bitfield const&, tr_bitfield const&>::Observer observer) = 0;
[[nodiscard]] virtual libtransmission::ObserverTag observe_got_bad_piece(
libtransmission::SimpleObservable<tr_torrent*, tr_piece_index_t>::Observer observer) = 0;
[[nodiscard]] virtual libtransmission::ObserverTag observe_got_bitfield(
libtransmission::SimpleObservable<tr_torrent*, tr_bitfield const&>::Observer observer) = 0;
[[nodiscard]] virtual libtransmission::ObserverTag observe_got_choke(
libtransmission::SimpleObservable<tr_torrent*, tr_bitfield const&>::Observer observer) = 0;
[[nodiscard]] virtual libtransmission::ObserverTag observe_got_have(
libtransmission::SimpleObservable<tr_torrent*, tr_piece_index_t>::Observer observer) = 0;
[[nodiscard]] virtual libtransmission::ObserverTag observe_got_have_all(
libtransmission::SimpleObservable<tr_torrent*>::Observer observer) = 0;
[[nodiscard]] virtual libtransmission::ObserverTag observe_got_reject(
libtransmission::SimpleObservable<tr_torrent*, tr_peer*, tr_block_index_t>::Observer observer) = 0;
[[nodiscard]] virtual libtransmission::ObserverTag observe_piece_completed(
libtransmission::SimpleObservable<tr_torrent*, tr_piece_index_t>::Observer observer) = 0;
[[nodiscard]] virtual libtransmission::ObserverTag observe_priority_changed(
libtransmission::SimpleObservable<tr_torrent*, tr_file_index_t const*, tr_file_index_t, tr_priority_t>::Observer
observer) = 0;
[[nodiscard]] virtual libtransmission::ObserverTag observe_sent_cancel(
libtransmission::SimpleObservable<tr_torrent*, tr_peer*, tr_block_index_t>::Observer observer) = 0;
[[nodiscard]] virtual libtransmission::ObserverTag observe_sent_request(
libtransmission::SimpleObservable<tr_torrent*, tr_peer*, tr_block_span_t>::Observer observer) = 0;
[[nodiscard]] virtual libtransmission::ObserverTag observe_sequential_download_changed(
libtransmission::SimpleObservable<tr_torrent*, bool>::Observer observer) = 0;
virtual ~Mediator() = default;
};
explicit Wishlist(Mediator& mediator_in);
~Wishlist();
// the next blocks that we should request from a peer
[[nodiscard]] std::vector<tr_block_span_t> next(
size_t n_wanted_blocks,
std::function<bool(tr_piece_index_t)> const& peer_has_piece);
private:
class Impl;
std::unique_ptr<Impl> impl_;
};