refactor!: remove per-peer parallel dialling (#2090)

maschad · achingbrain · commit 1f5a061fce0d · 2023-11-21T09:04:32.000Z
Since we are now dialling one peer at a time as a means of smarter dialling, we no longer need the option to control the concurrency of parallel dials across a single peers' multiaddrs. Closes #2090
diff --git a/doc/migrations/v0.46-v1.0.0.md b/doc/migrations/v0.46-v1.0.0.md
@@ -1,5 +1,5 @@
 <!--Specify versions for migration below-->
-# Migrating to libp2p@1.0.0 <!-- omit in toc -->
+# Migrating to libp2p@1.0 <!-- omit in toc -->
 
 A migration guide for refactoring your application code from libp2p `v0.46` to `v1.0.0`.
 
@@ -16,6 +16,7 @@ A migration guide for refactoring your application code from libp2p `v0.46` to `
 - [Plaintext](#plaintext)
 - [Pnet](#pnet)
 - [Metrics](#metrics)
+- [Connection Manager](#connection-manager)
 
 ## AutoNAT
 
@@ -311,3 +312,11 @@ The following metrics were renamed:
 
 `libp2p_dialler_pending_dials` => `libp2p_dial_queue_pending_dials`
 `libp2p_dialler_in_progress_dials` => `libp2p_dial_queue_in_progress_dials`
+
+## Connection Manager
+
+The observed behavior of dialing peers has been that given a list of supported addresses, if any one routable address would succeed then all would succeed and that if any routable address would fail then all would fail.
+
+Consequently the previous dial behaviour of dialing all available addresses (up to a concurrency limit) and cancelling any in-flight dials when the first succeeds was a very inefficient use of resources.
+
+Since `libp2p@0.46.10` we have only dialed one address at a time for each peer by setting the default value of the `ConnectionManager`'s `maxParallelDialsPerPeer` option to `1`.  As of `libp2p@1.0.0` this option has been removed.
diff --git a/packages/libp2p/src/connection-manager/constants.defaults.ts b/packages/libp2p/src/connection-manager/constants.defaults.ts
@@ -13,11 +13,6 @@ export const INBOUND_UPGRADE_TIMEOUT = 30e3
  */
 export const MAX_PEER_ADDRS_TO_DIAL = 25
 
-/**
- * @see https://libp2p.github.io/js-libp2p/interfaces/index._internal_.ConnectionManagerConfig.html#maxParallelDialsPerPeer
- */
-export const MAX_PARALLEL_DIALS_PER_PEER = 1
-
 /**
  * @see https://libp2p.github.io/js-libp2p/interfaces/index._internal_.ConnectionManagerConfig.html#autoDialInterval
  */
diff --git a/packages/libp2p/src/connection-manager/dial-queue.ts b/packages/libp2p/src/connection-manager/dial-queue.ts
@@ -12,7 +12,6 @@ import { codes } from '../errors.js'
 import { getPeerAddress } from '../get-peer.js'
 import {
   DIAL_TIMEOUT,
-  MAX_PARALLEL_DIALS_PER_PEER,
   MAX_PARALLEL_DIALS,
   MAX_PEER_ADDRS_TO_DIAL,
   LAST_DIAL_FAILURE_KEY
@@ -44,7 +43,6 @@ interface DialerInit {
   addressSorter?: AddressSorter
   maxParallelDials?: number
   maxPeerAddrsToDial?: number
-  maxParallelDialsPerPeer?: number
   dialTimeout?: number
   resolvers?: Record<string, Resolver>
   connections?: PeerMap<Connection[]>
@@ -54,7 +52,6 @@ const defaultOptions = {
   addressSorter: defaultAddressSort,
   maxParallelDials: MAX_PARALLEL_DIALS,
   maxPeerAddrsToDial: MAX_PEER_ADDRS_TO_DIAL,
-  maxParallelDialsPerPeer: MAX_PARALLEL_DIALS_PER_PEER,
   dialTimeout: DIAL_TIMEOUT,
   resolvers: {
     dnsaddr: dnsaddrResolver
@@ -79,7 +76,6 @@ export class DialQueue {
   private readonly transportManager: TransportManager
   private readonly addressSorter: AddressSorter
   private readonly maxPeerAddrsToDial: number
-  private readonly maxParallelDialsPerPeer: number
   private readonly dialTimeout: number
   private readonly inProgressDialCount?: Metric
   private readonly pendingDialCount?: Metric
@@ -90,7 +86,6 @@ export class DialQueue {
   constructor (components: DialQueueComponents, init: DialerInit = {}) {
     this.addressSorter = init.addressSorter ?? defaultOptions.addressSorter
     this.maxPeerAddrsToDial = init.maxPeerAddrsToDial ?? defaultOptions.maxPeerAddrsToDial
-    this.maxParallelDialsPerPeer = init.maxParallelDialsPerPeer ?? defaultOptions.maxParallelDialsPerPeer
     this.dialTimeout = init.dialTimeout ?? defaultOptions.dialTimeout
     this.connections = init.connections ?? new PeerMap()
     this.log = components.logger.forComponent('libp2p:connection-manager:dial-queue')
@@ -463,18 +458,10 @@ export class DialQueue {
     const dialAbortControllers: Array<(AbortController | undefined)> = pendingDial.multiaddrs.map(() => new AbortController())
 
     try {
-      let success = false
-
-      // internal peer dial queue to ensure we only dial the configured number of addresses
-      // per peer at the same time to prevent one peer with a lot of addresses swamping
-      // the dial queue
-      const peerDialQueue = new PQueue({
-        concurrency: this.maxParallelDialsPerPeer
-      })
+      // internal peer dial queue - only one dial per peer at a time
+      const peerDialQueue = new PQueue({ concurrency: 1 })
       peerDialQueue.on('error', (err) => {
-        if (!success) {
-          this.log.error('error dialling [%s] %o', pendingDial.multiaddrs, err)
-        }
+        this.log.error('error dialing [%s] %o', pendingDial.multiaddrs, err)
       })
 
       const conn = await Promise.any(pendingDial.multiaddrs.map(async (addr, i) => {
diff --git a/packages/libp2p/src/connection-manager/index.ts b/packages/libp2p/src/connection-manager/index.ts
@@ -9,7 +9,7 @@ import { codes } from '../errors.js'
 import { getPeerAddress } from '../get-peer.js'
 import { AutoDial } from './auto-dial.js'
 import { ConnectionPruner } from './connection-pruner.js'
-import { AUTO_DIAL_CONCURRENCY, AUTO_DIAL_MAX_QUEUE_LENGTH, AUTO_DIAL_PRIORITY, DIAL_TIMEOUT, INBOUND_CONNECTION_THRESHOLD, MAX_CONNECTIONS, MAX_INCOMING_PENDING_CONNECTIONS, MAX_PARALLEL_DIALS, MAX_PARALLEL_DIALS_PER_PEER, MAX_PEER_ADDRS_TO_DIAL, MIN_CONNECTIONS } from './constants.js'
+import { AUTO_DIAL_CONCURRENCY, AUTO_DIAL_MAX_QUEUE_LENGTH, AUTO_DIAL_PRIORITY, DIAL_TIMEOUT, INBOUND_CONNECTION_THRESHOLD, MAX_CONNECTIONS, MAX_INCOMING_PENDING_CONNECTIONS, MAX_PARALLEL_DIALS, MAX_PEER_ADDRS_TO_DIAL, MIN_CONNECTIONS } from './constants.js'
 import { DialQueue } from './dial-queue.js'
 import type { PendingDial, AddressSorter, Libp2pEvents, AbortOptions, ComponentLogger, Logger } from '@libp2p/interface'
 import type { Connection, MultiaddrConnection } from '@libp2p/interface/connection'
@@ -89,14 +89,6 @@ export interface ConnectionManagerInit {
    */
   maxParallelDials?: number
 
-  /**
-   * To prevent individual peers with large amounts of multiaddrs swamping the
-   * dial queue, this value controls how many addresses to dial in parallel per
-   * peer. So for example if two peers have 10 addresses and this value is set
-   * at 5, we will dial 5 addresses from each at a time. (default: 1)
-   */
-  maxParallelDialsPerPeer?: number
-
   /**
    * Maximum number of addresses allowed for a given peer - if a peer has more
    * addresses than this then the dial will fail. (default: 25)
@@ -260,7 +252,6 @@ export class DefaultConnectionManager implements ConnectionManager, Startable {
       addressSorter: init.addressSorter ?? defaultAddressSort,
       maxParallelDials: init.maxParallelDials ?? MAX_PARALLEL_DIALS,
       maxPeerAddrsToDial: init.maxPeerAddrsToDial ?? MAX_PEER_ADDRS_TO_DIAL,
-      maxParallelDialsPerPeer: init.maxParallelDialsPerPeer ?? MAX_PARALLEL_DIALS_PER_PEER,
       dialTimeout: init.dialTimeout ?? DIAL_TIMEOUT,
       resolvers: init.resolvers ?? {
         dnsaddr: dnsaddrResolver
diff --git a/packages/libp2p/test/connection-manager/dial-queue.spec.ts b/packages/libp2p/test/connection-manager/dial-queue.spec.ts
@@ -193,103 +193,6 @@ describe('dial queue', () => {
     expect(reject).to.have.property('callCount', addrs.length)
   })
 
-  it('should abort all dials when its signal is aborted', async () => {
-    const signals: Record<string, AbortSignal | undefined> = {}
-    const slowDial = async (): Promise<void> => {
-      await delay(1000)
-    }
-    const actions: Record<string, (...args: any[]) => Promise<any>> = {
-      '/ip4/127.0.0.1/tcp/1231': slowDial,
-      '/ip4/127.0.0.1/tcp/1232': slowDial,
-      '/ip4/127.0.0.1/tcp/1233': slowDial
-    }
-    const controller = new AbortController()
-
-    dialer = new DialQueue(components, {
-      maxParallelDials: 2,
-      maxParallelDialsPerPeer: 10
-    })
-
-    components.transportManager.transportForMultiaddr.returns(stubInterface<Transport>())
-    components.transportManager.dial.callsFake(async (ma, options = {}) => {
-      const maStr = ma.toString()
-      const action = actions[maStr]
-
-      if (action != null) {
-        signals[maStr] = options.signal
-        return action()
-      }
-
-      throw new Error(`No action found for multiaddr ${maStr}`)
-    })
-
-    setTimeout(() => { controller.abort() }, 100)
-
-    await expect(dialer.dial(Object.keys(actions).map(str => multiaddr(str)), {
-      signal: controller.signal
-    })).to.eventually.be.rejected
-      .with.property('name', 'CodeError')
-
-    expect(signals['/ip4/127.0.0.1/tcp/1231']).to.have.property('aborted', true)
-    expect(signals['/ip4/127.0.0.1/tcp/1232']).to.have.property('aborted', true)
-    expect(signals).to.not.have.property('/ip4/127.0.0.1/tcp/1233') // never dialled as above the maxParallelDials limit
-  })
-
-  it('should abort other dials when one succeeds', async () => {
-    const remotePeer = await createEd25519PeerId()
-    const connection1 = mockConnection(mockMultiaddrConnection(mockDuplex(), remotePeer))
-    const connection2 = mockConnection(mockMultiaddrConnection(mockDuplex(), remotePeer))
-    const connection3 = mockConnection(mockMultiaddrConnection(mockDuplex(), remotePeer))
-    const actions: Record<string, () => Promise<Connection>> = {
-      '/ip4/127.0.0.1/tcp/1231': async () => {
-        // Slow dial
-        await delay(1000)
-
-        return connection1
-      },
-      '/ip4/127.0.0.1/tcp/1232': async () => {
-        // Fast dial
-        await delay(10)
-
-        return connection2
-      },
-      '/ip4/127.0.0.1/tcp/1233': async () => {
-        // Slow dial
-        await delay(1000)
-
-        return connection3
-      }
-    }
-    const signals: Record<string, AbortSignal> = {}
-
-    components.transportManager.transportForMultiaddr.returns(stubInterface<Transport>())
-    components.transportManager.dial.callsFake(async (ma, opts = {}) => {
-      const maStr = ma.toString()
-      const action = actions[maStr]
-
-      if (action != null) {
-        signals[maStr] = opts.signal
-        return action()
-      }
-
-      throw new Error(`No action found for multiaddr ${maStr}`)
-    })
-
-    dialer = new DialQueue(components, {
-      maxParallelDials: 50,
-      maxParallelDialsPerPeer: 10
-    })
-
-    await expect(dialer.dial(Object.keys(actions).map(str => multiaddr(str)))).to.eventually.equal(connection2)
-
-    // Dial attempt finished without connection
-    expect(signals['/ip4/127.0.0.1/tcp/1231']).to.have.property('aborted', true)
-    // Dial attempt led to connection
-    expect(signals['/ip4/127.0.0.1/tcp/1232']).to.have.property('aborted', false)
-    // Dial attempt finished without connection
-    expect(signals['/ip4/127.0.0.1/tcp/1233']).to.have.property('aborted', true)
-  })
-
   it('should ignore DNS addresses for other peers', async () => {
     const remotePeer = await createEd25519PeerId()
     const otherRemotePeer = await createEd25519PeerId()
diff --git a/packages/libp2p/test/connection-manager/direct.node.ts b/packages/libp2p/test/connection-manager/direct.node.ts
@@ -22,7 +22,6 @@ import { MemoryDatastore } from 'datastore-core/memory'
 import delay from 'delay'
 import { pipe } from 'it-pipe'
 import { pushable } from 'it-pushable'
-import pDefer from 'p-defer'
 import pWaitFor from 'p-wait-for'
 import Sinon from 'sinon'
 import { stubInterface } from 'sinon-ts'
@@ -223,84 +222,57 @@ describe('dialing (direct, TCP)', () => {
       .and.to.have.property('code', ERR_TIMEOUT)
   })
 
-  it('should dial to the max concurrency', async () => {
-    const peerId = await createEd25519PeerId()
-    const addrs = [
-      multiaddr('/ip4/0.0.0.0/tcp/8000'),
-      multiaddr('/ip4/0.0.0.0/tcp/8001'),
-      multiaddr('/ip4/0.0.0.0/tcp/8002')
-    ]
+  it('should only dial to the max concurrency', async () => {
+    const peerId1 = await createEd25519PeerId()
+    const peerId2 = await createEd25519PeerId()
+    const peerId3 = await createEd25519PeerId()
+
+    const addr1 = multiaddr(`/ip4/127.0.0.1/tcp/1234/p2p/${peerId1}`)
+    const addr2 = multiaddr(`/ip4/127.0.12.4/tcp/3210/p2p/${peerId2}`)
+    const addr3 = multiaddr(`/ip4/123.3.11.1/tcp/2010/p2p/${peerId3}`)
+
+    const slowDial = async (): Promise<Connection> => {
+      await delay(100)
+      return mockConnection(mockMultiaddrConnection(mockDuplex(), peerId1))
+    }
+
+    const actions: Record<string, (...args: any[]) => Promise<any>> = {
+      [addr1.toString()]: slowDial,
+      [addr2.toString()]: slowDial,
+      [addr3.toString()]: async () => mockConnection(mockMultiaddrConnection(mockDuplex(), peerId3))
+    }
 
     const dialer = new DialQueue(localComponents, {
-      maxParallelDials: 2,
-      maxParallelDialsPerPeer: 10
+      maxParallelDials: 2
     })
 
-    const deferredDial = pDefer<Connection>()
     const transportManagerDialStub = Sinon.stub(localTM, 'dial')
-    transportManagerDialStub.callsFake(async () => deferredDial.promise)
+    transportManagerDialStub.callsFake(async ma => {
+      const maStr = ma.toString()
+      const action = actions[maStr]
 
-    // Perform 3 multiaddr dials
-    void dialer.dial(addrs)
-
-    // Let the call stack run
-    await delay(0)
+      if (action != null) {
+        return action()
+      }
 
-    // We should have 2 in progress, and 1 waiting
-    expect(transportManagerDialStub).to.have.property('callCount', 2)
+      throw new Error(`No action found for multiaddr ${maStr}`)
+    })
 
-    deferredDial.resolve(mockConnection(mockMultiaddrConnection(mockDuplex(), peerId)))
+    // dial 3 different peers
+    void Promise.all([
+      dialer.dial(addr1),
+      dialer.dial(addr2),
+      dialer.dial(addr3)
+    ])
 
     // Let the call stack run
     await delay(0)
 
-    // Only two dials should be executed, as the first dial will succeed
+    // We should have 2 in progress, and 1 waiting
     expect(transportManagerDialStub).to.have.property('callCount', 2)
-  })
 
-  it('should append the remote peerId to multiaddrs', async () => {
-    const addrs = [
-      multiaddr('/ip4/0.0.0.0/tcp/8000'),
-      multiaddr('/ip4/0.0.0.0/tcp/8001'),
-      multiaddr('/ip4/0.0.0.0/tcp/8002'),
-      multiaddr('/unix/tmp/some/path.sock')
-    ]
-
-    // Inject data into the AddressBook
-    await localComponents.peerStore.merge(remoteComponents.peerId, {
-      multiaddrs: addrs
-    })
-
-    const dialer = new DialQueue(localComponents, {
-      maxParallelDialsPerPeer: 10
-    })
-
-    const transportManagerDialStub = Sinon.stub(localTM, 'dial')
-    transportManagerDialStub.callsFake(async (ma) => {
-      await delay(10)
-      return mockConnection(mockMultiaddrConnection(mockDuplex(), remoteComponents.peerId))
-    })
-
-    // Perform dial
-    await dialer.dial(remoteComponents.peerId)
+    // stop dials
     dialer.stop()
-
-    // Dialled each address
-    expect(transportManagerDialStub).to.have.property('callCount', 4)
-
-    for (let i = 0; i < addrs.length; i++) {
-      const call = transportManagerDialStub.getCall(i)
-      const ma = call.args[0]
-
-      // should not append peerId to path multiaddrs
-      if (ma.toString().startsWith('/unix')) {
-        expect(ma.toString()).to.not.endWith(`/p2p/${remoteComponents.peerId.toString()}`)
-
-        continue
-      }
-
-      expect(ma.toString()).to.endWith(`/p2p/${remoteComponents.peerId.toString()}`)
-    }
   })
 })
 
diff --git a/packages/libp2p/test/connection-manager/direct.spec.ts b/packages/libp2p/test/connection-manager/direct.spec.ts
