nimbus-eth1/nimbus/sync/snap.nim

159 lines
5.0 KiB
Nim

# Nimbus - New sync approach - A fusion of snap, trie, beam and other methods
#
# Copyright (c) 2021 Status Research & Development GmbH
# Licensed under either of
# * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
# http://www.apache.org/licenses/LICENSE-2.0)
# * MIT license ([LICENSE-MIT](LICENSE-MIT) or
# http://opensource.org/licenses/MIT)
# at your option. This file may not be copied, modified, or distributed
# except according to those terms.
import
std/hashes,
chronicles,
chronos,
eth/[common/eth_types, p2p, p2p/peer_pool, p2p/private/p2p_types],
stew/keyed_queue,
"."/[protocol, types],
./snap/worker
{.push raises: [Defect].}
logScope:
topics = "snap-sync"
type
SnapSyncCtx* = ref object of Worker
chain: AbstractChainDB
buddies: KeyedQueue[Peer,WorkerBuddy] ## LRU cache with worker descriptors
pool: PeerPool ## for starting the system
# ------------------------------------------------------------------------------
# Private helpers
# ------------------------------------------------------------------------------
proc nsCtx(sp: WorkerBuddy): SnapSyncCtx =
sp.ns.SnapSyncCtx
proc hash(peer: Peer): Hash =
## Needed for `buddies` table key comparison
hash(peer.remote.id)
# ------------------------------------------------------------------------------
# Private functions
# ------------------------------------------------------------------------------
proc workerLoop(sp: WorkerBuddy) {.async.} =
let ns = sp.nsCtx
trace "Starting peer worker", peer=sp,
peers=ns.pool.len, workers=ns.buddies.len, maxWorkers=ns.buddiesMax
# Do something, work a bit
await sp.workerExec
# Continue until stopped
while not sp.ctrl.stopped:
# Rotate connection table so the most used entry is at the end
discard sp.nsCtx.buddies.lruFetch(sp.peer)
let delayMs = if sp.workerLockedOk: 1000 else: 50
await sleepAsync(chronos.milliseconds(delayMs))
# Do something, work a bit
await sp.workerExec
trace "Peer worker done", peer=sp, ctrlState=sp.ctrl.state,
peers=ns.pool.len, workers=ns.buddies.len, maxWorkers=ns.buddiesMax
proc onPeerConnected(ns: SnapSyncCtx, peer: Peer) =
let sp = WorkerBuddy.new(ns, peer)
# Check for known entry (which should not exist.)
if ns.buddies.hasKey(peer):
trace "Ignoring already registered peer!", peer,
peers=ns.pool.len, workers=ns.buddies.len, maxWorkers=ns.buddiesMax
return
# Initialise worker for this peer
if not sp.workerStart():
trace "Ignoring useless peer", peer,
peers=ns.pool.len, workers=ns.buddies.len, maxWorkers=ns.buddiesMax
sp.ctrl.zombie = true
return
# Check for table overflow. An overflow should not happen if the table is
# as large as the peer connection table.
if ns.buddiesMax <= ns.buddies.len:
let leastPeer = ns.buddies.shift.value.data
if leastPeer.ctrl.zombie:
trace "Dequeuing zombie peer", leastPeer,
peers=ns.pool.len, workers=ns.buddies.len, maxWorkers=ns.buddiesMax
discard
else:
trace "Peer table full! Dequeuing least used entry", leastPeer,
peers=ns.pool.len, workers=ns.buddies.len, maxWorkers=ns.buddiesMax
leastPeer.workerStop()
leastPeer.ctrl.zombie = true
# Add peer entry
discard ns.buddies.lruAppend(sp.peer, sp, ns.buddiesMax)
# Run worker
asyncSpawn sp.workerLoop()
proc onPeerDisconnected(ns: SnapSyncCtx, peer: Peer) =
let rc = ns.buddies.eq(peer)
if rc.isErr:
debug "Disconnected from unregistered peer", peer,
peers=ns.pool.len, workers=ns.buddies.len, maxWorkers=ns.buddiesMax
return
let sp = rc.value
if sp.ctrl.zombie:
trace "Disconnected zombie peer", peer,
peers=ns.pool.len, workers=ns.buddies.len, maxWorkers=ns.buddiesMax
else:
sp.workerStop()
ns.buddies.del(peer)
trace "Disconnected peer", peer,
peers=ns.pool.len, workers=ns.buddies.len, maxWorkers=ns.buddiesMax
# ------------------------------------------------------------------------------
# Public functions
# ------------------------------------------------------------------------------
proc new*(T: type SnapSyncCtx; ethNode: EthereumNode; maxPeers: int): T =
## Constructor
new result
let size = max(1,maxPeers)
result.chain = ethNode.chain
result.buddies.init(size)
result.buddiesMax = size
result.pool = ethNode.peerPool
proc start*(ctx: SnapSyncCtx) =
## Set up syncing. This call should come early.
var po = PeerObserver(
onPeerConnected:
proc(p: Peer) {.gcsafe.} =
ctx.onPeerConnected(p),
onPeerDisconnected:
proc(p: Peer) {.gcsafe.} =
ctx.onPeerDisconnected(p))
# Initialise sub-systems
ctx.workerSetup(ctx.chain)
po.setProtocol eth
ctx.pool.addObserver(ctx, po)
proc stop*(ctx: SnapSyncCtx) =
## Stop syncing
ctx.pool.delObserver(ctx)
ctx.workerRelease()
# ------------------------------------------------------------------------------
# End
# ------------------------------------------------------------------------------