opt-out support for v1.4.0 attestation stability subnets (#5128)

* opt-out support for v1.4.0 attestation stability subnets

* document debug-prefix-flag-policy and remove temporary from flag name

beacon_chain/conf.nim

@@ -238,6 +238,11 @@ type
       desc: "Number of worker threads (\"0\" = use as many threads as there are CPU cores available)"
       name: "num-threads" .}: int
 
+    useOldStabilitySubnets* {.
+      hidden
+      defaultValue: true
+      name: "debug-use-old-attestation-stability-subnets" .}: bool
+
     # https://github.com/ethereum/execution-apis/blob/v1.0.0-beta.3/src/engine/authentication.md#key-distribution
     jwtSecret* {.
       desc: "A file containing the hex-encoded 256 bit secret key to be used for verifying/generating JWT tokens"

beacon_chain/nimbus_beacon_node.nim

@@ -324,7 +324,8 @@ proc initFullNode(
     blobQuarantine = newClone(BlobQuarantine())
     consensusManager = ConsensusManager.new(
       dag, attestationPool, quarantine, node.elManager,
-      ActionTracker.init(rng, config.subscribeAllSubnets),
+      ActionTracker.init(rng, node.network.nodeId, config.subscribeAllSubnets,
+                         config.useOldStabilitySubnets),
       node.dynamicFeeRecipientsStore, config.validatorsDir,
       config.defaultFeeRecipient, config.suggestedGasLimit)
     blockProcessor = BlockProcessor.new(

beacon_chain/spec/presets.nim

@@ -23,7 +23,6 @@ const
 
   # Constants from `validator.md` not covered by config/presets in the spec
   TARGET_AGGREGATORS_PER_COMMITTEE*: uint64 = 16
-  RANDOM_SUBNETS_PER_VALIDATOR*: uint64 = 1
   EPOCHS_PER_RANDOM_SUBNET_SUBSCRIPTION*: uint64 = 256
 
 type
@@ -91,6 +90,7 @@ const
   ignoredValues = [
     "TRANSITION_TOTAL_DIFFICULTY", # Name that appears in some altair alphas, obsolete, remove when no more testnets
     "MIN_ANCHOR_POW_BLOCK_DIFFICULTY", # Name that appears in some altair alphas, obsolete, remove when no more testnets
+    "RANDOM_SUBNETS_PER_VALIDATOR",    # Removed in consensus-specs v1.4.0
   ]
 
 when const_preset == "mainnet":
@@ -562,7 +562,6 @@ proc readRuntimeConfig(
   checkCompatibility MAX_VOLUNTARY_EXITS
 
   checkCompatibility TARGET_AGGREGATORS_PER_COMMITTEE
-  checkCompatibility RANDOM_SUBNETS_PER_VALIDATOR
   checkCompatibility EPOCHS_PER_RANDOM_SUBNET_SUBSCRIPTION
   checkCompatibility ATTESTATION_SUBNET_COUNT
 

beacon_chain/validators/action_tracker.nim

@@ -6,11 +6,13 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  std/[sequtils, tables],
   stew/shims/[sets, hashes], chronicles,
   eth/p2p/discoveryv5/random2,
-  ../spec/forks,
-  ../consensus_object_pools/spec_cache
+  ../spec/forks
+
+from ../spec/validator import compute_subscribed_subnets
+from ../consensus_object_pools/spec_cache import
+  EpochRef, epoch, get_committee_assignments
 
 export forks, tables, sets
 
@@ -36,7 +38,9 @@ type
     slot*: Slot
 
   ActionTracker* = object
+    useOldStabilitySubnets: bool
     rng: ref HmacDrbgContext
+    nodeId: UInt256
 
     subscribeAllAttnets: bool
 
@@ -146,8 +150,12 @@ func stabilitySubnets*(tracker: ActionTracker, slot: Slot): AttnetBits =
     allSubnetBits
   else:
     var res: AttnetBits
+    if tracker.useOldStabilitySubnets:
       for v in tracker.stabilitySubnets:
         res[v.subnet_id.int] = true
+    else:
+      for subnetId in compute_subscribed_subnets(tracker.nodeId, slot.epoch):
+        res[subnetId.int] = true
     res
 
 proc updateSlot*(tracker: var ActionTracker, wallSlot: Slot) =
@@ -172,9 +180,6 @@ proc updateSlot*(tracker: var ActionTracker, wallSlot: Slot) =
     debug "Validator no longer active", index = k
     tracker.knownValidators.del k
 
-  # One stability subnet per known validator
-  static: doAssert RANDOM_SUBNETS_PER_VALIDATOR == 1
-
   # https://github.com/ethereum/consensus-specs/blob/v1.3.0/specs/phase0/validator.md#phase-0-attestation-subnet-stability
   let expectedSubnets =
     min(ATTESTATION_SUBNET_COUNT.int, tracker.knownValidators.len)
@@ -247,6 +252,8 @@ func needsUpdate*(
   tracker.attesterDepRoot !=
     state.dependent_root(if epoch > Epoch(0): epoch - 1 else: epoch)
 
+from std/sequtils import toSeq
+
 func updateActions*(
     tracker: var ActionTracker, epochRef: EpochRef) =
   # Updates the schedule for upcoming attestation and proposal work
@@ -293,9 +300,11 @@ func updateActions*(
         (1'u32 shl (slot mod SLOTS_PER_EPOCH))
 
 func init*(
-    T: type ActionTracker, rng: ref HmacDrbgContext,
-    subscribeAllAttnets: bool): T =
+    T: type ActionTracker, rng: ref HmacDrbgContext, nodeId: UInt256,
+    subscribeAllAttnets: bool, useOldStabilitySubnets: bool): T =
   T(
     rng: rng,
-    subscribeAllAttnets: subscribeAllAttnets
+    nodeId: nodeId,
+    subscribeAllAttnets: subscribeAllAttnets,
+    useOldStabilitySubnets: useOldStabilitySubnets
   )

docs/the_nimbus_book/src/options.md

@@ -127,6 +127,8 @@ The following options are available:
 ...
 ```
 
+Any `debug`-prefixed flags are considered ephemeral and subject to removal without notice.
+
 ## Configuration files
 
 All command line options can also be provided in a [TOML](https://toml.io/en/)

tests/test_action_tracker.nim

@@ -16,7 +16,7 @@ suite "subnet tracker":
     let rng = HmacDrbgContext.new()
 
   test "should register stability subnets on attester duties":
-    var tracker = ActionTracker.init(rng, false)
+    var tracker = ActionTracker.init(rng, default(UInt256), false, true)
 
     check:
       tracker.stabilitySubnets(Slot(0)).countOnes() == 0
@@ -62,7 +62,7 @@ suite "subnet tracker":
 
   test "should register sync committee duties":
     var
-      tracker = ActionTracker.init(rng, false)
+      tracker = ActionTracker.init(rng, default(UInt256), false, true)
       pk0 = ValidatorPubKey.fromHex("0xb4102a1f6c80e5c596a974ebd930c9f809c3587dc4d1d3634b77ff66db71e376dbc86c3252c6d140ce031f4ec6167798").get()
       pk1 = ValidatorPubKey.fromHex("0xa00d2954717425ce047e0928e5f4ec7c0e3bbe1058db511303fd659770ddace686ee2e22ac180422e516f4c503eb2228").get()