12x speedup on state sim with 100k validators sans BLS by caching get_beacon_proposer_index(...)

beacon_chain/spec/datatypes.nim

@@ -399,11 +399,11 @@ type
     data*: BeaconState
     root*: Eth2Digest # hash_tree_root(data)
 
-  # TODO remove some of these, or otherwise coordinate with EpochRef
   StateCache* = object
     shuffled_active_validator_indices*:
       Table[Epoch, seq[ValidatorIndex]]
     committee_count_cache*: Table[Epoch, uint64]
+    beacon_proposer_indices*: Table[Slot, Option[ValidatorIndex]]
 
 func shortValidatorKey*(state: BeaconState, validatorIdx: int): string =
     ($state.validators[validatorIdx].pubkey)[0..7]

beacon_chain/spec/validator.nim

@@ -196,6 +196,12 @@ func compute_proposer_index(state: BeaconState, indices: seq[ValidatorIndex],
 # https://github.com/ethereum/eth2.0-specs/blob/v0.11.3/specs/phase0/beacon-chain.md#get_beacon_proposer_index
 func get_beacon_proposer_index*(state: BeaconState, cache: var StateCache, slot: Slot):
     Option[ValidatorIndex] =
+  try:
+    if slot in cache.beacon_proposer_indices:
+      return cache.beacon_proposer_indices[slot]
+  except KeyError:
+    raiseAssert("Cached entries are added before use")
+
   # Return the beacon proposer index at the current slot.
   let epoch = get_current_epoch(state)
 
@@ -215,14 +221,16 @@ func get_beacon_proposer_index*(state: BeaconState, cache: var StateCache, slot:
       indices =
         sorted(cache.shuffled_active_validator_indices[epoch], system.cmp)
 
+    cache.beacon_proposer_indices[slot] =
       compute_proposer_index(state, indices, seed)
+    cache.beacon_proposer_indices[slot]
   except KeyError:
     raiseAssert("Cached entries are added before use")
 
 # https://github.com/ethereum/eth2.0-specs/blob/v0.11.3/specs/phase0/beacon-chain.md#get_beacon_proposer_index
-func get_beacon_proposer_index*(state: BeaconState, stateCache: var StateCache):
+func get_beacon_proposer_index*(state: BeaconState, cache: var StateCache):
     Option[ValidatorIndex] =
-  get_beacon_proposer_index(state, stateCache, state.slot)
+  get_beacon_proposer_index(state, cache, state.slot)
 
 # Not from spec
 # TODO: cache the results from this and reuse in subsequent calls to get_beacon_proposer_index

beacon_chain/state_transition.nim

@@ -273,11 +273,11 @@ proc makeBeaconBlock*(
     graffiti: Eth2Digest,
     attestations: seq[Attestation],
     deposits: seq[Deposit],
-    rollback: RollbackHashedProc): Option[BeaconBlock] =
+    rollback: RollbackHashedProc,
+    cache: var StateCache): Option[BeaconBlock] =
   ## Create a block for the given state. The last block applied to it must be
   ## the one identified by parent_root and process_slots must be called up to
   ## the slot for which a block is to be created.
-  var cache = get_empty_per_epoch_cache()
 
   # To create a block, we'll first apply a partial block to the state, skipping
   # some validations.

beacon_chain/validator_duties.nim

@@ -176,6 +176,7 @@ proc makeBeaconBlockForHeadAndSlot*(node: BeaconNode,
       doAssert v.addr == addr poolPtr.tmpState.data
       poolPtr.tmpState = poolPtr.headState
 
+    var cache = get_empty_per_epoch_cache()
     let message = makeBeaconBlock(
       hashedState,
       validator_index,
@@ -185,7 +186,8 @@ proc makeBeaconBlockForHeadAndSlot*(node: BeaconNode,
       graffiti,
       node.attestationPool.getAttestationsForBlock(state),
       deposits,
-      restore)
+      restore,
+      cache)
 
     if message.isSome():
       # TODO this restore is needed because otherwise tmpState will be internally

ncli/ncli_query.nim

@@ -1,8 +1,7 @@
 import
   confutils, os, strutils, json_serialization,
   stew/byteutils,
-  ../beacon_chain/spec/[crypto, datatypes],
+  ../beacon_chain/spec/[crypto, datatypes]
-  ../beacon_chain/ssz/dynamic_navigator
 
 type
   QueryCmd* = enum

research/block_sim.nim

@@ -117,7 +117,8 @@ cli do(slots = SLOTS_PER_EPOCH * 6,
           Eth2Digest(),
           attPool.getAttestationsForBlock(state),
           @[],
-          noRollback)
+          noRollback,
+          cache)
 
       var
         newBlock = SignedBeaconBlock(

research/state_sim.nim

@@ -95,7 +95,8 @@ cli do(slots = SLOTS_PER_EPOCH * 6,
 
     withTimer(timers[t]):
       signedBlock = addTestBlock(
-        state[], latest_block_root, attestations = blockAttestations, flags = flags)
+        state[], latest_block_root, cache, attestations = blockAttestations,
+        flags = flags)
     latest_block_root = withTimerRet(timers[tHashBlock]):
       hash_tree_root(signedBlock.message)
 

tests/test_attestation_pool.nim

@@ -149,8 +149,9 @@ suiteReport "Attestation pool processing" & preset():
       attestations.len == 1
 
   timedTest "Fork choice returns latest block with no attestations":
+    var cache = get_empty_per_epoch_cache()
     let
-      b1 = addTestBlock(state.data, blockPool.tail.root)
+      b1 = addTestBlock(state.data, blockPool.tail.root, cache)
       b1Root = hash_tree_root(b1.message)
       b1Add = blockPool.add(b1Root, b1)[]
       head = pool.selectHead()
@@ -159,7 +160,7 @@ suiteReport "Attestation pool processing" & preset():
       head == b1Add
 
     let
-      b2 = addTestBlock(state.data, b1Root)
+      b2 = addTestBlock(state.data, b1Root, cache)
       b2Root = hash_tree_root(b2.message)
       b2Add = blockPool.add(b2Root, b2)[]
       head2 = pool.selectHead()
@@ -170,7 +171,7 @@ suiteReport "Attestation pool processing" & preset():
   timedTest "Fork choice returns block with attestation":
     var cache = get_empty_per_epoch_cache()
     let
-      b10 = makeTestBlock(state.data, blockPool.tail.root)
+      b10 = makeTestBlock(state.data, blockPool.tail.root, cache)
       b10Root = hash_tree_root(b10.message)
       b10Add = blockPool.add(b10Root, b10)[]
       head = pool.selectHead()
@@ -179,7 +180,7 @@ suiteReport "Attestation pool processing" & preset():
       head == b10Add
 
     let
-      b11 = makeTestBlock(state.data, blockPool.tail.root,
+      b11 = makeTestBlock(state.data, blockPool.tail.root, cache,
         graffiti = Eth2Digest(data: [1'u8, 0, 0, 0 ,0 ,0 ,0 ,0 ,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
       )
       b11Root = hash_tree_root(b11.message)

tests/test_block_pool.nim

@@ -10,7 +10,7 @@
 import
   options, sequtils, unittest,
   ./testutil, ./testblockutil,
-  ../beacon_chain/spec/[datatypes, digest, helpers],
+  ../beacon_chain/spec/[datatypes, digest, helpers, validator],
   ../beacon_chain/[beacon_node_types, block_pool, state_transition, ssz]
 
 suiteReport "BlockRef and helpers" & preset():
@@ -88,9 +88,10 @@ suiteReport "Block pool processing" & preset():
       db = makeTestDB(SLOTS_PER_EPOCH)
       pool = BlockPool.init(db)
       stateData = newClone(pool.loadTailState())
-      b1 = addTestBlock(stateData.data, pool.tail.root)
+      cache = get_empty_per_epoch_cache()
+      b1 = addTestBlock(stateData.data, pool.tail.root, cache)
       b1Root = hash_tree_root(b1.message)
-      b2 = addTestBlock(stateData.data, b1Root)
+      b2 = addTestBlock(stateData.data, b1Root, cache)
       b2Root {.used.} = hash_tree_root(b2.message)
 
   timedTest "getRef returns nil for missing blocks":
@@ -132,7 +133,7 @@ suiteReport "Block pool processing" & preset():
       process_slots(stateData.data, stateData.data.data.slot + 1)
 
     let
-      b4 = addTestBlock(stateData.data, b2Root)
+      b4 = addTestBlock(stateData.data, b2Root, cache)
       b4Root = hash_tree_root(b4.message)
       b4Add = pool.add(b4Root, b4)[]
 
@@ -284,12 +285,13 @@ when const_preset == "minimal":  # These require some minutes in mainnet
       var
         db = makeTestDB(SLOTS_PER_EPOCH)
         pool = BlockPool.init(db)
+        cache = get_empty_per_epoch_cache()
 
     timedTest "prune heads on finalization" & preset():
       block:
         # Create a fork that will not be taken
         var
-          blck = makeTestBlock(pool.headState.data, pool.head.blck.root)
+          blck = makeTestBlock(pool.headState.data, pool.head.blck.root, cache)
         check: pool.add(hash_tree_root(blck.message), blck).isOk
 
       for i in 0 ..< (SLOTS_PER_EPOCH * 6):
@@ -299,9 +301,8 @@ when const_preset == "minimal":  # These require some minutes in mainnet
             pool.tail.children.len == 2
             pool.heads.len == 2
         var
-          cache = get_empty_per_epoch_cache()
           blck = makeTestBlock(
-            pool.headState.data, pool.head.blck.root,
+            pool.headState.data, pool.head.blck.root, cache,
             attestations = makeFullAttestations(
               pool.headState.data.data, pool.head.blck.root,
               pool.headState.data.data.slot, cache, {}))
@@ -332,7 +333,7 @@ when const_preset == "minimal":  # These require some minutes in mainnet
       for i in 0 ..< (SLOTS_PER_EPOCH * 6 - 2):
         var
           blck = makeTestBlock(
-            pool.headState.data, pool.head.blck.root,
+            pool.headState.data, pool.head.blck.root, cache,
             attestations = makeFullAttestations(
               pool.headState.data.data, pool.head.blck.root,
               pool.headState.data.data.slot, cache, {}))
@@ -345,7 +346,7 @@ when const_preset == "minimal":  # These require some minutes in mainnet
           pool.headState.data, Slot(SLOTS_PER_EPOCH * 6 + 2) )
 
       var blck = makeTestBlock(
-        pool.headState.data, pool.head.blck.root,
+        pool.headState.data, pool.head.blck.root, cache,
         attestations = makeFullAttestations(
           pool.headState.data.data, pool.head.blck.root,
           pool.headState.data.data.slot, cache, {}))

tests/test_state_transition.nim

@@ -36,7 +36,8 @@ suiteReport "Block processing" & preset():
   timedTest "Passes from genesis state, empty block" & preset():
     var
       previous_block_root = hash_tree_root(genesisBlock.message)
-      new_block = makeTestBlock(state[], previous_block_root)
+      cache = get_empty_per_epoch_cache()
+      new_block = makeTestBlock(state[], previous_block_root, cache)
 
     let block_ok = state_transition(state[], new_block, {}, noRollback)
 
@@ -53,9 +54,10 @@ suiteReport "Block processing" & preset():
   timedTest "Passes through epoch update, empty block" & preset():
     var
       previous_block_root = genesisRoot
+      cache = get_empty_per_epoch_cache()
 
     for i in 1..SLOTS_PER_EPOCH.int:
-      let new_block = makeTestBlock(state[], previous_block_root)
+      let new_block = makeTestBlock(state[], previous_block_root, cache)
 
       let block_ok = state_transition(state[], new_block, {}, noRollback)
 
@@ -90,7 +92,7 @@ suiteReport "Block processing" & preset():
         state[], GENESIS_SLOT + MIN_ATTESTATION_INCLUSION_DELAY + 1)
 
     let
-      new_block = makeTestBlock(state[], previous_block_root,
+      new_block = makeTestBlock(state[], previous_block_root, cache,
         attestations = @[attestation]
       )
     check state_transition(state[], new_block, {}, noRollback)

tests/testblockutil.nim

@@ -89,13 +89,13 @@ func signBlock*(
 proc addTestBlock*(
     state: var HashedBeaconState,
     parent_root: Eth2Digest,
+    cache: var StateCache,
     eth1_data = Eth1Data(),
     attestations = newSeq[Attestation](),
     deposits = newSeq[Deposit](),
     graffiti = Eth2Digest(),
     flags: set[UpdateFlag] = {}): SignedBeaconBlock =
   # Create and add a block to state - state will advance by one slot!
-  var cache = get_empty_per_epoch_cache()
   advance_slot(state, err(Opt[Eth2Digest]), flags, cache)
 
   let
@@ -122,7 +122,8 @@ proc addTestBlock*(
       graffiti,
       attestations,
       deposits,
-      noRollback)
+      noRollback,
+      cache)
 
   doAssert message.isSome(), "Should have created a valid block!"
 
@@ -136,6 +137,7 @@ proc addTestBlock*(
 proc makeTestBlock*(
     state: HashedBeaconState,
     parent_root: Eth2Digest,
+    cache: var StateCache,
     eth1_data = Eth1Data(),
     attestations = newSeq[Attestation](),
     deposits = newSeq[Deposit](),
@@ -147,7 +149,8 @@ proc makeTestBlock*(
   # because the block includes the state root.
   var tmpState = newClone(state)
   addTestBlock(
-    tmpState[], parent_root, eth1_data, attestations, deposits, graffiti, flags)
+    tmpState[], parent_root, cache, eth1_data, attestations, deposits,
+    graffiti, flags)
 
 proc makeAttestation*(
     state: BeaconState, beacon_block_root: Eth2Digest,