reduce LC optsync latency

AllTests-mainnet.md

@@ -56,17 +56,6 @@ OK: 6/6 Fail: 0/6 Skip: 0/6
 + basics                                                                                     OK
 ```
 OK: 1/1 Fail: 0/1 Skip: 0/1
-## Block clearance (light client) [Preset: mainnet]
-```diff
-+ Delayed finality update                                                                    OK
-+ Error conditions                                                                           OK
-+ Incremental sync                                                                           OK
-+ Initial sync                                                                               OK
-+ Low slot numbers                                                                           OK
-+ Reorg                                                                                      OK
-+ Reverse incremental sync                                                                   OK
-```
-OK: 7/7 Fail: 0/7 Skip: 0/7
 ## Block pool altair processing [Preset: mainnet]
 ```diff
 + Invalid signatures [Preset: mainnet]                                                       OK
@@ -590,4 +579,4 @@ OK: 1/1 Fail: 0/1 Skip: 0/1
 OK: 9/9 Fail: 0/9 Skip: 0/9
 
 ---TOTAL---
-OK: 331/336 Fail: 0/336 Skip: 5/336
+OK: 324/329 Fail: 0/329 Skip: 5/329

beacon_chain/beacon_node.nim

@@ -15,15 +15,15 @@ import
 
   # Local modules
   "."/[beacon_clock, beacon_chain_db, conf, light_client],
-  ./gossip_processing/[eth2_processor, block_processor],
+  ./gossip_processing/[eth2_processor, block_processor, optimistic_processor],
   ./networking/eth2_network,
   ./eth1/eth1_monitor,
   ./consensus_object_pools/[
     blockchain_dag, block_quarantine, consensus_manager, exit_pool,
     attestation_pool, sync_committee_msg_pool],
   ./spec/datatypes/[base, altair],
   ./spec/eth2_apis/dynamic_fee_recipients,
-  ./sync/[optimistic_sync_light_client, sync_manager, request_manager],
+  ./sync/[sync_manager, request_manager],
   ./validators/[
     action_tracker, message_router, validator_monitor, validator_pool,
     keystore_management],
@@ -33,9 +33,9 @@ export
   osproc, chronos, httpserver, presto, action_tracker,
   beacon_clock, beacon_chain_db, conf, light_client,
   attestation_pool, sync_committee_msg_pool, validator_pool,
-  eth2_network, eth1_monitor, optimistic_sync_light_client,
-  request_manager, sync_manager, eth2_processor, blockchain_dag,
-  block_quarantine, base, exit_pool,  message_router, validator_monitor,
+  eth2_network, eth1_monitor, request_manager, sync_manager,
+  eth2_processor, optimistic_processor, blockchain_dag, block_quarantine,
+  base, exit_pool,  message_router, validator_monitor,
   consensus_manager, dynamic_fee_recipients
 
 type
@@ -58,7 +58,7 @@ type
     db*: BeaconChainDB
     config*: BeaconNodeConf
     attachedValidators*: ref ValidatorPool
-    lcOptSync*: LCOptimisticSync
+    optimisticProcessor*: OptimisticProcessor
     lightClient*: LightClient
     dag*: ChainDAGRef
     quarantine*: ref Quarantine
@@ -83,6 +83,7 @@ type
     consensusManager*: ref ConsensusManager
     attachedValidatorBalanceTotal*: uint64
     gossipState*: GossipState
+    blocksGossipState*: GossipState
     beaconClock*: BeaconClock
     restKeysCache*: Table[ValidatorPubKey, ValidatorIndex]
     validatorMonitor*: ref ValidatorMonitor

beacon_chain/beacon_node_light_client.nim

@@ -16,6 +16,24 @@ import
 
 logScope: topics = "beacnde"
 
+func shouldSyncOptimistically*(node: BeaconNode, wallSlot: Slot): bool =
+  # Check whether light client is used for syncing
+  let optimisticHeader = node.lightClient.optimisticHeader.valueOr:
+    return false
+
+  # Check whether light client is sufficiently ahead of DAG
+  const minProgress = 8 * SLOTS_PER_EPOCH  # Set arbitrarily
+  let dagSlot = getStateField(node.dag.headState, slot)
+  if dagSlot + minProgress > optimisticHeader.slot:
+    return false
+
+  # Check whether light client has synced sufficiently close to wall slot
+  const maxAge = 2 * SLOTS_PER_EPOCH
+  if optimisticHeader.slot < max(wallSlot, maxAge.Slot) - maxAge:
+    return false
+
+  true
+
 proc initLightClient*(
     node: BeaconNode,
     rng: ref HmacDrbgContext,
@@ -30,52 +48,28 @@ proc initLightClient*(
   # for broadcasting light client data as a server.
 
   let
-    optimisticProcessor = proc(signedBlock: ForkedMsgTrustedSignedBeaconBlock):
+    optimisticHandler = proc(signedBlock: ForkedMsgTrustedSignedBeaconBlock):
         Future[void] {.async.} =
       debug "New LC optimistic block",
         opt = signedBlock.toBlockId(),
         dag = node.dag.head.bid,
         wallSlot = node.currentSlot
       return
-    optSync = initLCOptimisticSync(
-      node.network, getBeaconTime, optimisticProcessor,
-      config.safeSlotsToImportOptimistically)
+    optimisticProcessor = initOptimisticProcessor(
+      getBeaconTime, optimisticHandler)
 
     lightClient = createLightClient(
       node.network, rng, config, cfg, forkDigests, getBeaconTime,
       genesis_validators_root, LightClientFinalizationMode.Strict)
 
   if config.lightClientEnable:
-    proc shouldSyncOptimistically(slot: Slot): bool =
-      const
-        # Minimum number of slots to be ahead of DAG to use optimistic sync
-        minProgress = 8 * SLOTS_PER_EPOCH
-        # Maximum age of light client optimistic header to use optimistic sync
-        maxAge = 2 * SLOTS_PER_EPOCH
-
-      if slot < getStateField(node.dag.headState, slot) + minProgress:
-        false
-      elif getBeaconTime().slotOrZero > slot + maxAge:
-        false
-      else:
-        true
-
-    proc onFinalizedHeader(lightClient: LightClient) =
-      let optimisticHeader = lightClient.optimisticHeader.valueOr:
-        return
-      if not shouldSyncOptimistically(optimisticHeader.slot):
-        return
-      let finalizedHeader = lightClient.finalizedHeader.valueOr:
-        return
-      optSync.setOptimisticHeader(optimisticHeader)
-      optSync.setFinalizedHeader(finalizedHeader)
+    proc onFinalizedHeader(
+        lightClient: LightClient, finalizedHeader: BeaconBlockHeader) =
+      optimisticProcessor.setFinalizedHeader(finalizedHeader)
 
-    proc onOptimisticHeader(lightClient: LightClient) =
-      let optimisticHeader = lightClient.optimisticHeader.valueOr:
-        return
-      if not shouldSyncOptimistically(optimisticHeader.slot):
-        return
-      optSync.setOptimisticHeader(optimisticHeader)
+    proc onOptimisticHeader(
+        lightClient: LightClient, optimisticHeader: BeaconBlockHeader) =
+      optimisticProcessor.setOptimisticHeader(optimisticHeader)
 
     lightClient.onFinalizedHeader = onFinalizedHeader
     lightClient.onOptimisticHeader = onOptimisticHeader
@@ -86,14 +80,13 @@ proc initLightClient*(
       lightClientEnable = config.lightClientEnable,
       lightClientTrustedBlockRoot = config.lightClientTrustedBlockRoot
 
-  node.lcOptSync = optSync
+  node.optimisticProcessor = optimisticProcessor
   node.lightClient = lightClient
 
 proc startLightClient*(node: BeaconNode) =
   if not node.config.lightClientEnable:
     return
 
-  node.lcOptSync.start()
   node.lightClient.start()
 
 proc installLightClientMessageValidators*(node: BeaconNode) =

beacon_chain/conf_light_client.nim

@@ -133,12 +133,6 @@ type LightClientConf* = object
     desc: "A file containing the hex-encoded 256 bit secret key to be used for verifying/generating JWT tokens"
     name: "jwt-secret" .}: Option[string]
 
-  safeSlotsToImportOptimistically* {.
-    hidden
-    desc: "Modify SAFE_SLOTS_TO_IMPORT_OPTIMISTICALLY"
-    defaultValue: 128
-    name: "safe-slots-to-import-optimistically" .}: uint16
-
   # Testing
   stopAtEpoch* {.
     hidden