udp: remove swarm worker and related logic

This commit is contained in:
Joakim Frostegård 2024-02-10 11:40:11 +01:00
parent a2e1dd4eef
commit 7fa143964e
7 changed files with 4 additions and 1082 deletions

View file

@ -1,13 +1,9 @@
use std::collections::BTreeMap;
use std::hash::Hash;
use std::iter::repeat_with; use std::iter::repeat_with;
use std::sync::atomic::AtomicUsize; use std::sync::atomic::AtomicUsize;
use std::sync::Arc; use std::sync::Arc;
use crossbeam_channel::{Receiver, SendError, Sender, TrySendError};
use aquatic_common::access_list::AccessListArcSwap; use aquatic_common::access_list::AccessListArcSwap;
use aquatic_common::{CanonicalSocketAddr, ServerStartInstant}; use aquatic_common::ServerStartInstant;
use aquatic_udp_protocol::*; use aquatic_udp_protocol::*;
use crossbeam_utils::CachePadded; use crossbeam_utils::CachePadded;
use hdrhistogram::Histogram; use hdrhistogram::Histogram;
@ -33,141 +29,6 @@ impl IpVersion {
} }
} }
#[derive(Clone, Copy, Debug)]
pub struct SocketWorkerIndex(pub usize);
#[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)]
pub struct SwarmWorkerIndex(pub usize);
impl SwarmWorkerIndex {
pub fn from_info_hash(config: &Config, info_hash: InfoHash) -> Self {
Self(info_hash.0[0] as usize % config.swarm_workers)
}
}
#[derive(Debug)]
pub struct PendingScrapeRequest {
pub slab_key: usize,
pub info_hashes: BTreeMap<usize, InfoHash>,
}
#[derive(Debug)]
pub struct PendingScrapeResponse {
pub slab_key: usize,
pub torrent_stats: BTreeMap<usize, TorrentScrapeStatistics>,
}
#[derive(Debug)]
pub enum ConnectedRequest {
Announce(AnnounceRequest),
Scrape(PendingScrapeRequest),
}
#[derive(Debug)]
pub enum ConnectedResponse {
AnnounceIpv4(AnnounceResponse<Ipv4AddrBytes>),
AnnounceIpv6(AnnounceResponse<Ipv6AddrBytes>),
Scrape(PendingScrapeResponse),
}
pub struct ConnectedRequestSender {
index: SocketWorkerIndex,
senders: Vec<Sender<(SocketWorkerIndex, ConnectedRequest, CanonicalSocketAddr)>>,
}
impl ConnectedRequestSender {
pub fn new(
index: SocketWorkerIndex,
senders: Vec<Sender<(SocketWorkerIndex, ConnectedRequest, CanonicalSocketAddr)>>,
) -> Self {
Self { index, senders }
}
pub fn try_send_to(
&self,
index: SwarmWorkerIndex,
request: ConnectedRequest,
addr: CanonicalSocketAddr,
) -> Result<(), (SwarmWorkerIndex, ConnectedRequest, CanonicalSocketAddr)> {
match self.senders[index.0].try_send((self.index, request, addr)) {
Ok(()) => Ok(()),
Err(TrySendError::Full(r)) => Err((index, r.1, r.2)),
Err(TrySendError::Disconnected(_)) => {
panic!("Request channel {} is disconnected", index.0);
}
}
}
}
pub struct ConnectedResponseSender {
senders: Vec<Sender<(CanonicalSocketAddr, ConnectedResponse)>>,
to_any_last_index_picked: usize,
}
impl ConnectedResponseSender {
pub fn new(senders: Vec<Sender<(CanonicalSocketAddr, ConnectedResponse)>>) -> Self {
Self {
senders,
to_any_last_index_picked: 0,
}
}
pub fn try_send_to(
&self,
index: SocketWorkerIndex,
addr: CanonicalSocketAddr,
response: ConnectedResponse,
) -> Result<(), TrySendError<(CanonicalSocketAddr, ConnectedResponse)>> {
self.senders[index.0].try_send((addr, response))
}
pub fn send_to(
&self,
index: SocketWorkerIndex,
addr: CanonicalSocketAddr,
response: ConnectedResponse,
) -> Result<(), SendError<(CanonicalSocketAddr, ConnectedResponse)>> {
self.senders[index.0].send((addr, response))
}
pub fn send_to_any(
&mut self,
addr: CanonicalSocketAddr,
response: ConnectedResponse,
) -> Result<(), SendError<(CanonicalSocketAddr, ConnectedResponse)>> {
let start = self.to_any_last_index_picked + 1;
let mut message = Some((addr, response));
for i in (start..start + self.senders.len()).map(|i| i % self.senders.len()) {
match self.senders[i].try_send(message.take().unwrap()) {
Ok(()) => {
self.to_any_last_index_picked = i;
return Ok(());
}
Err(TrySendError::Full(msg)) => {
message = Some(msg);
}
Err(TrySendError::Disconnected(_)) => {
panic!("ConnectedResponseReceiver disconnected");
}
}
}
let (addr, response) = message.unwrap();
self.to_any_last_index_picked = start % self.senders.len();
self.send_to(
SocketWorkerIndex(self.to_any_last_index_picked),
addr,
response,
)
}
}
pub type ConnectedResponseReceiver = Receiver<(CanonicalSocketAddr, ConnectedResponse)>;
#[derive(Clone)] #[derive(Clone)]
pub struct Statistics { pub struct Statistics {
pub socket: Vec<CachePaddedArc<IpVersionStatistics<SocketWorkerStatistics>>>, pub socket: Vec<CachePaddedArc<IpVersionStatistics<SocketWorkerStatistics>>>,

View file

@ -3,13 +3,12 @@ pub mod config;
pub mod swarm; pub mod swarm;
pub mod workers; pub mod workers;
use std::collections::BTreeMap;
use std::thread::{sleep, Builder, JoinHandle}; use std::thread::{sleep, Builder, JoinHandle};
use std::time::Duration; use std::time::Duration;
use anyhow::Context; use anyhow::Context;
use aquatic_common::WorkerType; use aquatic_common::WorkerType;
use crossbeam_channel::{bounded, unbounded}; use crossbeam_channel::unbounded;
use signal_hook::consts::SIGUSR1; use signal_hook::consts::SIGUSR1;
use signal_hook::iterator::Signals; use signal_hook::iterator::Signals;
@ -18,14 +17,9 @@ use aquatic_common::access_list::update_access_list;
use aquatic_common::cpu_pinning::{pin_current_if_configured_to, WorkerIndex}; use aquatic_common::cpu_pinning::{pin_current_if_configured_to, WorkerIndex};
use aquatic_common::privileges::PrivilegeDropper; use aquatic_common::privileges::PrivilegeDropper;
use common::{ use common::{State, Statistics};
ConnectedRequestSender, ConnectedResponseSender, SocketWorkerIndex, State, Statistics,
SwarmWorkerIndex,
};
use config::Config; use config::Config;
use swarm::TorrentMaps;
use workers::socket::ConnectionValidator; use workers::socket::ConnectionValidator;
use workers::swarm::SwarmWorker;
pub const APP_NAME: &str = "aquatic_udp: UDP BitTorrent tracker"; pub const APP_NAME: &str = "aquatic_udp: UDP BitTorrent tracker";
pub const APP_VERSION: &str = env!("CARGO_PKG_VERSION"); pub const APP_VERSION: &str = env!("CARGO_PKG_VERSION");

View file

@ -1,3 +1,2 @@
pub mod socket; pub mod socket;
pub mod statistics; pub mod statistics;
pub mod swarm;

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@ -1,5 +1,4 @@
mod mio; mod mio;
mod storage;
#[cfg(all(target_os = "linux", feature = "io-uring"))] #[cfg(all(target_os = "linux", feature = "io-uring"))]
mod uring; mod uring;
mod validator; mod validator;
@ -11,8 +10,7 @@ use socket2::{Domain, Protocol, Socket, Type};
use crate::{ use crate::{
common::{ common::{
CachePaddedArc, ConnectedRequestSender, ConnectedResponseReceiver, IpVersionStatistics, CachePaddedArc, IpVersionStatistics, SocketWorkerStatistics, State, StatisticsMessage,
SocketWorkerStatistics, State, StatisticsMessage,
}, },
config::Config, config::Config,
}; };

View file

@ -1,218 +0,0 @@
use std::collections::BTreeMap;
use hashbrown::HashMap;
use slab::Slab;
use aquatic_common::{SecondsSinceServerStart, ValidUntil};
use aquatic_udp_protocol::*;
use crate::common::*;
use crate::config::Config;
#[derive(Debug)]
pub struct PendingScrapeResponseSlabEntry {
num_pending: usize,
valid_until: ValidUntil,
torrent_stats: BTreeMap<usize, TorrentScrapeStatistics>,
transaction_id: TransactionId,
}
#[derive(Default)]
pub struct PendingScrapeResponseSlab(Slab<PendingScrapeResponseSlabEntry>);
impl PendingScrapeResponseSlab {
pub fn prepare_split_requests(
&mut self,
config: &Config,
request: ScrapeRequest,
valid_until: ValidUntil,
) -> impl IntoIterator<Item = (SwarmWorkerIndex, PendingScrapeRequest)> {
let capacity = config.swarm_workers.min(request.info_hashes.len());
let mut split_requests: HashMap<SwarmWorkerIndex, PendingScrapeRequest> =
HashMap::with_capacity(capacity);
if request.info_hashes.is_empty() {
::log::warn!(
"Attempted to prepare PendingScrapeResponseSlab entry with zero info hashes"
);
return split_requests;
}
let vacant_entry = self.0.vacant_entry();
let slab_key = vacant_entry.key();
for (i, info_hash) in request.info_hashes.into_iter().enumerate() {
let split_request = split_requests
.entry(SwarmWorkerIndex::from_info_hash(config, info_hash))
.or_insert_with(|| PendingScrapeRequest {
slab_key,
info_hashes: BTreeMap::new(),
});
split_request.info_hashes.insert(i, info_hash);
}
vacant_entry.insert(PendingScrapeResponseSlabEntry {
num_pending: split_requests.len(),
valid_until,
torrent_stats: Default::default(),
transaction_id: request.transaction_id,
});
split_requests
}
pub fn add_and_get_finished(
&mut self,
response: &PendingScrapeResponse,
) -> Option<ScrapeResponse> {
let finished = if let Some(entry) = self.0.get_mut(response.slab_key) {
entry.num_pending -= 1;
entry.torrent_stats.extend(response.torrent_stats.iter());
entry.num_pending == 0
} else {
::log::warn!(
"PendingScrapeResponseSlab.add didn't find entry for key {:?}",
response.slab_key
);
false
};
if finished {
let entry = self.0.remove(response.slab_key);
Some(ScrapeResponse {
transaction_id: entry.transaction_id,
torrent_stats: entry.torrent_stats.into_values().collect(),
})
} else {
None
}
}
pub fn clean(&mut self, now: SecondsSinceServerStart) {
self.0.retain(|k, v| {
if v.valid_until.valid(now) {
true
} else {
::log::warn!(
"Unconsumed PendingScrapeResponseSlab entry. {:?}: {:?}",
k,
v
);
false
}
});
self.0.shrink_to_fit();
}
}
#[cfg(test)]
mod tests {
use aquatic_common::ServerStartInstant;
use quickcheck::TestResult;
use quickcheck_macros::quickcheck;
use super::*;
#[quickcheck]
fn test_pending_scrape_response_slab(
request_data: Vec<(i32, i64, u8)>,
swarm_workers: u8,
) -> TestResult {
if swarm_workers == 0 {
return TestResult::discard();
}
let config = Config {
swarm_workers: swarm_workers as usize,
..Default::default()
};
let valid_until = ValidUntil::new(ServerStartInstant::new(), 1);
let mut map = PendingScrapeResponseSlab::default();
let mut requests = Vec::new();
for (t, c, b) in request_data {
if b == 0 {
return TestResult::discard();
}
let mut info_hashes = Vec::new();
for i in 0..b {
let info_hash = InfoHash([i; 20]);
info_hashes.push(info_hash);
}
let request = ScrapeRequest {
transaction_id: TransactionId::new(t),
connection_id: ConnectionId::new(c),
info_hashes,
};
requests.push(request);
}
let mut all_split_requests = Vec::new();
for request in requests.iter() {
let split_requests =
map.prepare_split_requests(&config, request.to_owned(), valid_until);
all_split_requests.push(
split_requests
.into_iter()
.collect::<Vec<(SwarmWorkerIndex, PendingScrapeRequest)>>(),
);
}
assert_eq!(map.0.len(), requests.len());
let mut responses = Vec::new();
for split_requests in all_split_requests {
for (worker_index, split_request) in split_requests {
assert!(worker_index.0 < swarm_workers as usize);
let torrent_stats = split_request
.info_hashes
.into_iter()
.map(|(i, info_hash)| {
(
i,
TorrentScrapeStatistics {
seeders: NumberOfPeers::new((info_hash.0[0]) as i32),
leechers: NumberOfPeers::new(0),
completed: NumberOfDownloads::new(0),
},
)
})
.collect();
let response = PendingScrapeResponse {
slab_key: split_request.slab_key,
torrent_stats,
};
if let Some(response) = map.add_and_get_finished(&response) {
responses.push(response);
}
}
}
assert!(map.0.is_empty());
assert_eq!(responses.len(), requests.len());
TestResult::from_bool(true)
}
}

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@ -1,149 +0,0 @@
mod storage;
use std::net::IpAddr;
use std::sync::atomic::Ordering;
use std::time::Duration;
use std::time::Instant;
use crossbeam_channel::Receiver;
use crossbeam_channel::Sender;
use rand::{rngs::SmallRng, SeedableRng};
use aquatic_common::{CanonicalSocketAddr, ValidUntil};
use crate::common::*;
use crate::config::Config;
use storage::TorrentMaps;
pub struct SwarmWorker {
pub config: Config,
pub state: State,
pub statistics: CachePaddedArc<IpVersionStatistics<SwarmWorkerStatistics>>,
pub request_receiver: Receiver<(SocketWorkerIndex, ConnectedRequest, CanonicalSocketAddr)>,
pub response_sender: ConnectedResponseSender,
pub statistics_sender: Sender<StatisticsMessage>,
pub worker_index: SwarmWorkerIndex,
}
impl SwarmWorker {
pub fn run(&mut self) -> anyhow::Result<()> {
let mut torrents = TorrentMaps::default();
let mut rng = SmallRng::from_entropy();
let timeout = Duration::from_millis(self.config.request_channel_recv_timeout_ms);
let mut peer_valid_until = ValidUntil::new(
self.state.server_start_instant,
self.config.cleaning.max_peer_age,
);
let cleaning_interval = Duration::from_secs(self.config.cleaning.torrent_cleaning_interval);
let statistics_update_interval = Duration::from_secs(self.config.statistics.interval);
let mut last_cleaning = Instant::now();
let mut last_statistics_update = Instant::now();
let mut iter_counter = 0usize;
loop {
if let Ok((sender_index, request, src)) = self.request_receiver.recv_timeout(timeout) {
// It is OK to block here as long as we don't also do blocking
// sends in socket workers (doing both could cause a deadlock)
match (request, src.get().ip()) {
(ConnectedRequest::Announce(request), IpAddr::V4(ip)) => {
let response = torrents
.ipv4
.0
.entry(request.info_hash)
.or_default()
.announce(
&self.config,
&self.statistics_sender,
&mut rng,
&request,
ip.into(),
peer_valid_until,
);
// It doesn't matter which socket worker receives announce responses
self.response_sender
.send_to_any(src, ConnectedResponse::AnnounceIpv4(response))
.expect("swarm response channel is closed");
}
(ConnectedRequest::Announce(request), IpAddr::V6(ip)) => {
let response = torrents
.ipv6
.0
.entry(request.info_hash)
.or_default()
.announce(
&self.config,
&self.statistics_sender,
&mut rng,
&request,
ip.into(),
peer_valid_until,
);
// It doesn't matter which socket worker receives announce responses
self.response_sender
.send_to_any(src, ConnectedResponse::AnnounceIpv6(response))
.expect("swarm response channel is closed");
}
(ConnectedRequest::Scrape(request), IpAddr::V4(_)) => {
let response = torrents.ipv4.scrape(request);
self.response_sender
.send_to(sender_index, src, ConnectedResponse::Scrape(response))
.expect("swarm response channel is closed");
}
(ConnectedRequest::Scrape(request), IpAddr::V6(_)) => {
let response = torrents.ipv6.scrape(request);
self.response_sender
.send_to(sender_index, src, ConnectedResponse::Scrape(response))
.expect("swarm response channel is closed");
}
};
}
// Run periodic tasks
if iter_counter % 128 == 0 {
let now = Instant::now();
peer_valid_until = ValidUntil::new(
self.state.server_start_instant,
self.config.cleaning.max_peer_age,
);
if now > last_cleaning + cleaning_interval {
torrents.clean_and_update_statistics(
&self.config,
&self.state,
&self.statistics,
&self.statistics_sender,
&self.state.access_list,
);
last_cleaning = now;
}
if self.config.statistics.active()
&& now > last_statistics_update + statistics_update_interval
{
self.statistics
.ipv4
.torrents
.store(torrents.ipv4.num_torrents(), Ordering::Relaxed);
self.statistics
.ipv6
.torrents
.store(torrents.ipv6.num_torrents(), Ordering::Relaxed);
last_statistics_update = now;
}
}
iter_counter = iter_counter.wrapping_add(1);
}
}
}

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@ -1,563 +0,0 @@
use std::sync::atomic::Ordering;
use std::sync::Arc;
use aquatic_common::IndexMap;
use aquatic_common::SecondsSinceServerStart;
use aquatic_common::{
access_list::{create_access_list_cache, AccessListArcSwap, AccessListCache, AccessListMode},
ValidUntil,
};
use aquatic_udp_protocol::*;
use arrayvec::ArrayVec;
use crossbeam_channel::Sender;
use hdrhistogram::Histogram;
use rand::prelude::SmallRng;
use rand::Rng;
use crate::common::*;
use crate::config::Config;
const SMALL_PEER_MAP_CAPACITY: usize = 2;
pub struct TorrentMaps {
pub ipv4: TorrentMap<Ipv4AddrBytes>,
pub ipv6: TorrentMap<Ipv6AddrBytes>,
}
impl Default for TorrentMaps {
fn default() -> Self {
Self {
ipv4: TorrentMap(Default::default()),
ipv6: TorrentMap(Default::default()),
}
}
}
impl TorrentMaps {
/// Remove forbidden or inactive torrents, reclaim space and update statistics
pub fn clean_and_update_statistics(
&mut self,
config: &Config,
state: &State,
statistics: &CachePaddedArc<IpVersionStatistics<SwarmWorkerStatistics>>,
statistics_sender: &Sender<StatisticsMessage>,
access_list: &Arc<AccessListArcSwap>,
) {
let mut cache = create_access_list_cache(access_list);
let mode = config.access_list.mode;
let now = state.server_start_instant.seconds_elapsed();
let ipv4 =
self.ipv4
.clean_and_get_statistics(config, statistics_sender, &mut cache, mode, now);
let ipv6 =
self.ipv6
.clean_and_get_statistics(config, statistics_sender, &mut cache, mode, now);
if config.statistics.active() {
statistics.ipv4.peers.store(ipv4.0, Ordering::Relaxed);
statistics.ipv6.peers.store(ipv6.0, Ordering::Relaxed);
if let Some(message) = ipv4.1.map(StatisticsMessage::Ipv4PeerHistogram) {
if let Err(err) = statistics_sender.try_send(message) {
::log::error!("couldn't send statistics message: {:#}", err);
}
}
if let Some(message) = ipv6.1.map(StatisticsMessage::Ipv6PeerHistogram) {
if let Err(err) = statistics_sender.try_send(message) {
::log::error!("couldn't send statistics message: {:#}", err);
}
}
}
}
}
#[derive(Default)]
pub struct TorrentMap<I: Ip>(pub IndexMap<InfoHash, TorrentData<I>>);
impl<I: Ip> TorrentMap<I> {
pub fn scrape(&mut self, request: PendingScrapeRequest) -> PendingScrapeResponse {
let torrent_stats = request
.info_hashes
.into_iter()
.map(|(i, info_hash)| {
let stats = self
.0
.get(&info_hash)
.map(|torrent_data| torrent_data.scrape_statistics())
.unwrap_or_else(|| TorrentScrapeStatistics {
seeders: NumberOfPeers::new(0),
leechers: NumberOfPeers::new(0),
completed: NumberOfDownloads::new(0),
});
(i, stats)
})
.collect();
PendingScrapeResponse {
slab_key: request.slab_key,
torrent_stats,
}
}
/// Remove forbidden or inactive torrents, reclaim space and return number of remaining peers
fn clean_and_get_statistics(
&mut self,
config: &Config,
statistics_sender: &Sender<StatisticsMessage>,
access_list_cache: &mut AccessListCache,
access_list_mode: AccessListMode,
now: SecondsSinceServerStart,
) -> (usize, Option<Histogram<u64>>) {
let mut total_num_peers = 0;
let mut opt_histogram: Option<Histogram<u64>> = if config.statistics.torrent_peer_histograms
{
match Histogram::new(3) {
Ok(histogram) => Some(histogram),
Err(err) => {
::log::error!("Couldn't create peer histogram: {:#}", err);
None
}
}
} else {
None
};
self.0.retain(|info_hash, torrent| {
if !access_list_cache
.load()
.allows(access_list_mode, &info_hash.0)
{
return false;
}
let num_peers = match torrent {
TorrentData::Small(peer_map) => {
peer_map.clean_and_get_num_peers(config, statistics_sender, now)
}
TorrentData::Large(peer_map) => {
let num_peers =
peer_map.clean_and_get_num_peers(config, statistics_sender, now);
if let Some(peer_map) = peer_map.try_shrink() {
*torrent = TorrentData::Small(peer_map);
}
num_peers
}
};
total_num_peers += num_peers;
match opt_histogram {
Some(ref mut histogram) if num_peers > 0 => {
let n = num_peers.try_into().expect("Couldn't fit usize into u64");
if let Err(err) = histogram.record(n) {
::log::error!("Couldn't record {} to histogram: {:#}", n, err);
}
}
_ => (),
}
num_peers > 0
});
self.0.shrink_to_fit();
(total_num_peers, opt_histogram)
}
pub fn num_torrents(&self) -> usize {
self.0.len()
}
}
pub enum TorrentData<I: Ip> {
Small(SmallPeerMap<I>),
Large(LargePeerMap<I>),
}
impl<I: Ip> TorrentData<I> {
pub fn announce(
&mut self,
config: &Config,
statistics_sender: &Sender<StatisticsMessage>,
rng: &mut SmallRng,
request: &AnnounceRequest,
ip_address: I,
valid_until: ValidUntil,
) -> AnnounceResponse<I> {
let max_num_peers_to_take: usize = if request.peers_wanted.0.get() <= 0 {
config.protocol.max_response_peers
} else {
::std::cmp::min(
config.protocol.max_response_peers,
request.peers_wanted.0.get().try_into().unwrap(),
)
};
let status =
PeerStatus::from_event_and_bytes_left(request.event.into(), request.bytes_left);
let peer_map_key = ResponsePeer {
ip_address,
port: request.port,
};
// Create the response before inserting the peer. This means that we
// don't have to filter it out from the response peers, and that the
// reported number of seeders/leechers will not include it
let (response, opt_removed_peer) = match self {
Self::Small(peer_map) => {
let opt_removed_peer = peer_map.remove(&peer_map_key);
let (seeders, leechers) = peer_map.num_seeders_leechers();
let response = AnnounceResponse {
fixed: AnnounceResponseFixedData {
transaction_id: request.transaction_id,
announce_interval: AnnounceInterval::new(
config.protocol.peer_announce_interval,
),
leechers: NumberOfPeers::new(leechers.try_into().unwrap_or(i32::MAX)),
seeders: NumberOfPeers::new(seeders.try_into().unwrap_or(i32::MAX)),
},
peers: peer_map.extract_response_peers(max_num_peers_to_take),
};
// Convert peer map to large variant if it is full and
// announcing peer is not stopped and will therefore be
// inserted
if peer_map.is_full() && status != PeerStatus::Stopped {
*self = Self::Large(peer_map.to_large());
}
(response, opt_removed_peer)
}
Self::Large(peer_map) => {
let opt_removed_peer = peer_map.remove_peer(&peer_map_key);
let (seeders, leechers) = peer_map.num_seeders_leechers();
let response = AnnounceResponse {
fixed: AnnounceResponseFixedData {
transaction_id: request.transaction_id,
announce_interval: AnnounceInterval::new(
config.protocol.peer_announce_interval,
),
leechers: NumberOfPeers::new(leechers.try_into().unwrap_or(i32::MAX)),
seeders: NumberOfPeers::new(seeders.try_into().unwrap_or(i32::MAX)),
},
peers: peer_map.extract_response_peers(rng, max_num_peers_to_take),
};
// Try shrinking the map if announcing peer is stopped and
// will therefore not be inserted
if status == PeerStatus::Stopped {
if let Some(peer_map) = peer_map.try_shrink() {
*self = Self::Small(peer_map);
}
}
(response, opt_removed_peer)
}
};
match status {
PeerStatus::Leeching | PeerStatus::Seeding => {
let peer = Peer {
peer_id: request.peer_id,
is_seeder: status == PeerStatus::Seeding,
valid_until,
};
match self {
Self::Small(peer_map) => peer_map.insert(peer_map_key, peer),
Self::Large(peer_map) => peer_map.insert(peer_map_key, peer),
}
if config.statistics.peer_clients && opt_removed_peer.is_none() {
statistics_sender
.try_send(StatisticsMessage::PeerAdded(request.peer_id))
.expect("statistics channel should be unbounded");
}
}
PeerStatus::Stopped => {
if config.statistics.peer_clients && opt_removed_peer.is_some() {
statistics_sender
.try_send(StatisticsMessage::PeerRemoved(request.peer_id))
.expect("statistics channel should be unbounded");
}
}
};
response
}
pub fn scrape_statistics(&self) -> TorrentScrapeStatistics {
let (seeders, leechers) = match self {
Self::Small(peer_map) => peer_map.num_seeders_leechers(),
Self::Large(peer_map) => peer_map.num_seeders_leechers(),
};
TorrentScrapeStatistics {
seeders: NumberOfPeers::new(seeders.try_into().unwrap_or(i32::MAX)),
leechers: NumberOfPeers::new(leechers.try_into().unwrap_or(i32::MAX)),
completed: NumberOfDownloads::new(0),
}
}
}
impl<I: Ip> Default for TorrentData<I> {
fn default() -> Self {
Self::Small(SmallPeerMap(ArrayVec::default()))
}
}
/// Store torrents with up to two peers without an extra heap allocation
///
/// On public open trackers, this is likely to be the majority of torrents.
#[derive(Default, Debug)]
pub struct SmallPeerMap<I: Ip>(ArrayVec<(ResponsePeer<I>, Peer), SMALL_PEER_MAP_CAPACITY>);
impl<I: Ip> SmallPeerMap<I> {
fn is_full(&self) -> bool {
self.0.is_full()
}
fn num_seeders_leechers(&self) -> (usize, usize) {
let seeders = self.0.iter().filter(|(_, p)| p.is_seeder).count();
let leechers = self.0.len() - seeders;
(seeders, leechers)
}
fn insert(&mut self, key: ResponsePeer<I>, peer: Peer) {
self.0.push((key, peer));
}
fn remove(&mut self, key: &ResponsePeer<I>) -> Option<Peer> {
for (i, (k, _)) in self.0.iter().enumerate() {
if k == key {
return Some(self.0.remove(i).1);
}
}
None
}
fn extract_response_peers(&self, max_num_peers_to_take: usize) -> Vec<ResponsePeer<I>> {
Vec::from_iter(self.0.iter().take(max_num_peers_to_take).map(|(k, _)| *k))
}
fn clean_and_get_num_peers(
&mut self,
config: &Config,
statistics_sender: &Sender<StatisticsMessage>,
now: SecondsSinceServerStart,
) -> usize {
self.0.retain(|(_, peer)| {
let keep = peer.valid_until.valid(now);
if !keep
&& config.statistics.peer_clients
&& statistics_sender
.try_send(StatisticsMessage::PeerRemoved(peer.peer_id))
.is_err()
{
// Should never happen in practice
::log::error!("Couldn't send StatisticsMessage::PeerRemoved");
}
keep
});
self.0.len()
}
fn to_large(&self) -> LargePeerMap<I> {
let (num_seeders, _) = self.num_seeders_leechers();
let peers = self.0.iter().copied().collect();
LargePeerMap { peers, num_seeders }
}
}
#[derive(Default)]
pub struct LargePeerMap<I: Ip> {
peers: IndexMap<ResponsePeer<I>, Peer>,
num_seeders: usize,
}
impl<I: Ip> LargePeerMap<I> {
fn num_seeders_leechers(&self) -> (usize, usize) {
(self.num_seeders, self.peers.len() - self.num_seeders)
}
fn insert(&mut self, key: ResponsePeer<I>, peer: Peer) {
if peer.is_seeder {
self.num_seeders += 1;
}
self.peers.insert(key, peer);
}
fn remove_peer(&mut self, key: &ResponsePeer<I>) -> Option<Peer> {
let opt_removed_peer = self.peers.swap_remove(key);
if let Some(Peer {
is_seeder: true, ..
}) = opt_removed_peer
{
self.num_seeders -= 1;
}
opt_removed_peer
}
/// Extract response peers
///
/// If there are more peers in map than `max_num_peers_to_take`, do a random
/// selection of peers from first and second halves of map in order to avoid
/// returning too homogeneous peers.
///
/// Does NOT filter out announcing peer.
pub fn extract_response_peers(
&self,
rng: &mut impl Rng,
max_num_peers_to_take: usize,
) -> Vec<ResponsePeer<I>> {
if self.peers.len() <= max_num_peers_to_take {
self.peers.keys().copied().collect()
} else {
let middle_index = self.peers.len() / 2;
let num_to_take_per_half = max_num_peers_to_take / 2;
let offset_half_one = {
let from = 0;
let to = usize::max(1, middle_index - num_to_take_per_half);
rng.gen_range(from..to)
};
let offset_half_two = {
let from = middle_index;
let to = usize::max(middle_index + 1, self.peers.len() - num_to_take_per_half);
rng.gen_range(from..to)
};
let end_half_one = offset_half_one + num_to_take_per_half;
let end_half_two = offset_half_two + num_to_take_per_half;
let mut peers = Vec::with_capacity(max_num_peers_to_take);
if let Some(slice) = self.peers.get_range(offset_half_one..end_half_one) {
peers.extend(slice.keys());
}
if let Some(slice) = self.peers.get_range(offset_half_two..end_half_two) {
peers.extend(slice.keys());
}
peers
}
}
fn clean_and_get_num_peers(
&mut self,
config: &Config,
statistics_sender: &Sender<StatisticsMessage>,
now: SecondsSinceServerStart,
) -> usize {
self.peers.retain(|_, peer| {
let keep = peer.valid_until.valid(now);
if !keep {
if peer.is_seeder {
self.num_seeders -= 1;
}
if config.statistics.peer_clients
&& statistics_sender
.try_send(StatisticsMessage::PeerRemoved(peer.peer_id))
.is_err()
{
// Should never happen in practice
::log::error!("Couldn't send StatisticsMessage::PeerRemoved");
}
}
keep
});
if !self.peers.is_empty() {
self.peers.shrink_to_fit();
}
self.peers.len()
}
fn try_shrink(&mut self) -> Option<SmallPeerMap<I>> {
(self.peers.len() <= SMALL_PEER_MAP_CAPACITY).then(|| {
SmallPeerMap(ArrayVec::from_iter(
self.peers.iter().map(|(k, v)| (*k, *v)),
))
})
}
}
#[derive(Clone, Copy, Debug)]
struct Peer {
peer_id: PeerId,
is_seeder: bool,
valid_until: ValidUntil,
}
#[derive(PartialEq, Eq, Hash, Clone, Copy, Debug)]
pub enum PeerStatus {
Seeding,
Leeching,
Stopped,
}
impl PeerStatus {
/// Determine peer status from announce event and number of bytes left.
///
/// Likely, the last branch will be taken most of the time.
#[inline]
pub fn from_event_and_bytes_left(event: AnnounceEvent, bytes_left: NumberOfBytes) -> Self {
if event == AnnounceEvent::Stopped {
Self::Stopped
} else if bytes_left.0.get() == 0 {
Self::Seeding
} else {
Self::Leeching
}
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_peer_status_from_event_and_bytes_left() {
use PeerStatus::*;
let f = PeerStatus::from_event_and_bytes_left;
assert_eq!(Stopped, f(AnnounceEvent::Stopped, NumberOfBytes::new(0)));
assert_eq!(Stopped, f(AnnounceEvent::Stopped, NumberOfBytes::new(1)));
assert_eq!(Seeding, f(AnnounceEvent::Started, NumberOfBytes::new(0)));
assert_eq!(Leeching, f(AnnounceEvent::Started, NumberOfBytes::new(1)));
assert_eq!(Seeding, f(AnnounceEvent::Completed, NumberOfBytes::new(0)));
assert_eq!(Leeching, f(AnnounceEvent::Completed, NumberOfBytes::new(1)));
assert_eq!(Seeding, f(AnnounceEvent::None, NumberOfBytes::new(0)));
assert_eq!(Leeching, f(AnnounceEvent::None, NumberOfBytes::new(1)));
}
}