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crate::ix!();
pub trait EvictExtraOutboundPeers {
fn evict_extra_outbound_peers(
self: Arc<Self>,
time_in_seconds: OffsetDateTime);
}
impl EvictExtraOutboundPeers for PeerManager {
/**
| If we have extra outbound peers, try
| to disconnect the one with the oldest
| block announcement
|
*/
#[EXCLUSIVE_LOCKS_REQUIRED(CS_MAIN)]
fn evict_extra_outbound_peers(
self: Arc<Self>,
time_in_seconds: OffsetDateTime)
{
// If we have any extra block-relay-only
// peers, disconnect the youngest unless
// it's given us a block -- in which case,
// compare with the second-youngest, and
// out of those two, disconnect the peer
// who least recently gave us a block.
//
// The youngest block-relay-only peer
// would be the extra peer we connected to
// temporarily in order to sync our tip;
// see net.cpp.
//
// Note that we use higher nodeid as
// a measure for most recent connection.
if self.connman.get().get_extra_block_relay_count() > 0 {
let mut youngest_peer: (NodeId,i64) = (-1,0);
let mut next_youngest_peer: (NodeId,i64) = (-1,0);
let mut maybe_update_youngest_peer = move |pnode: Amo<Box<dyn NodeInterface>>| {
if !pnode.get().is_block_only_conn() || pnode.get().marked_for_disconnect() {
return;
}
if pnode.get().get_id() > youngest_peer.0 {
next_youngest_peer = youngest_peer;
youngest_peer.0 = pnode.get().get_id();
youngest_peer.1 = pnode.get().n_last_block_time().unwrap().unix_timestamp();
}
};
self.connman
.get_mut()
.for_each_node_mut(&mut maybe_update_youngest_peer);
let mut to_disconnect: NodeId = youngest_peer.0;
if youngest_peer.1 > next_youngest_peer.1 {
// Our newest block-relay-only
// peer gave us a block more
// recently; disconnect our second
// youngest.
to_disconnect = next_youngest_peer.0;
}
let mut maybe_mark_disconnect = move |pnode: Amo<Box<dyn NodeInterface>>| {
// EXCLUSIVE_LOCKS_REQUIRED(::CS_MAIN)
assert_lock_held!(CS_MAIN);
// Make sure we're not getting
// a block right now, and that
// we've been connected long
// enough for this eviction to
// happen at all.
//
// Note that we only request
// blocks from a peer if we learn
// of a valid headers chain with
// at least as much work as our
// tip.
let node_state: Amo<NodeState>
= create_state(pnode.get().get_id());
if node_state.is_none()
|| (time_in_seconds - pnode.get().n_time_connected().unwrap() >= MINIMUM_CONNECT_TIME
&& node_state.get().n_blocks_in_flight.load(atomic::Ordering::Relaxed) == 0)
{
pnode.get().mark_for_disconnect();
log_print!(
LogFlags::NET,
"disconnecting extra block-relay-only peer=%d (last block received at time %d)\n",
pnode.get_id(),
pnode.n_last_block_time
);
return true;
} else {
log_print!(
LogFlags::NET,
"keeping block-relay-only peer=%d chosen for eviction (connect time: %d, blocks_in_flight: %d)\n",
pnode.get_id(),
pnode.n_time_connected,
(*node_state).n_blocks_in_flight
);
}
return false;
};
self.connman.get_mut().for_node_mut(
to_disconnect,
&mut maybe_mark_disconnect
);
};
// Check whether we have too many
// outbound-full-relay peers
if self.connman.get().get_extra_full_outbound_count() > 0 {
// If we have more outbound-full-relay
// peers than we target, disconnect
// one.
//
// Pick the outbound-full-relay peer
// that least recently announced us
// a new block, with ties broken by
// choosing the more recent connection
// (higher node id)
let mut worst_peer: NodeId = -1;
let mut oldest_block_announcement: Option<OffsetDateTime>
= OffsetDateTime::from_unix_timestamp(max_unix_timestamp()).ok();
let mut maybe_mark_worst_peer = move |pnode: Amo<Box<dyn NodeInterface>>| -> () {
// EXCLUSIVE_LOCKS_REQUIRED(::CS_MAIN)
assert_lock_held!(CS_MAIN);
// Only consider
// outbound-full-relay peers that
// are not already marked for
// disconnection
if !pnode.get().is_full_outbound_conn()
|| pnode.get().marked_for_disconnect()
{
return;
}
let state: Amo<NodeState> = create_state(pnode.get().get_id());
// shouldn't be possible, but just
// in case
if state.is_none() {
return;
}
// Don't evict our protected peers
if state.get().chain_sync.protect {
return;
}
let last_block_announcement = state.get().last_block_announcement;
if {
let gate0 = last_block_announcement < oldest_block_announcement;
let gate1a = last_block_announcement == oldest_block_announcement;
let gate1b = pnode.get().get_id() > worst_peer;
let gate1 = gate1a && gate1b;
gate0 || gate1
}
{
worst_peer = pnode.get().get_id();
oldest_block_announcement = state.get().last_block_announcement;
}
};
self.connman.get_mut().for_each_node_mut(&mut maybe_mark_worst_peer);
if worst_peer != -1 {
let mut maybe_mark_disconnect = move |pnode: Amo<Box<dyn NodeInterface>>| {
// EXCLUSIVE_LOCKS_REQUIRED(::CS_MAIN)
assert_lock_held!(CS_MAIN);
// Only disconnect a peer that
// has been connected to us
// for some reasonable
// fraction of our
// check-frequency, to give it
// time for new information to
// have arrived.
//
// Also don't disconnect any
// peer we're trying to
// download a block from.
let created_state = create_state(pnode.get().get_id());
let state = created_state.get();
let time_connected = pnode.get().n_time_connected().unwrap();
if time_in_seconds - time_connected > MINIMUM_CONNECT_TIME
&& state.n_blocks_in_flight.load(atomic::Ordering::Relaxed) == 0
{
log_print!(
LogFlags::NET,
"disconnecting extra outbound peer=%d (last block announcement received at time %d)\n",
pnode.get_id(),
oldest_block_announcement
);
pnode.get().mark_for_disconnect();
return true;
} else {
log_print!(
LogFlags::NET,
"keeping outbound peer=%d chosen for eviction (connect time: %d, blocks_in_flight: %d)\n",
pnode.get_id(),
pnode.n_time_connected,
state.n_blocks_in_flight
);
return false;
}
};
let disconnected: bool
= self.connman.get_mut().for_node_mut(
worst_peer,
&mut maybe_mark_disconnect
);
if disconnected {
// If we disconnected an extra
// peer, that means we
// successfully connected to
// at least one peer after the
// last time we detected
// a stale tip. Don't try any
// more extra peers until we
// next detect a stale tip, to
// limit the load we put on
// the network from these
// extra connections.
self.connman.get_mut().set_try_new_outbound_peer(false);
}
}
}
}
}