core: extract state.ReadDurations triple

Replace the {Account, Storage, Code} time.Duration scalars threaded through
ProcessResultWithMetrics, txExecResult, processBlockPreTx and resultHandler
with a single ReadDurations struct + Add merge primitive. Same shape as
StateCounts. Adds (*StateDB).SnapshotReads() helper at the boundary.

core/blockchain.go

@@ -689,9 +689,9 @@ func (bc *BlockChain) processBlockWithAccessList(parentRoot common.Hash, block *
 		prefetchAccountReads, prefetchStorageReads = pr.PrefetchReadTimes()
 	}
 	balAccountReads, balStorageReads := stateTransition.ReadTimes()
-	stats.AccountReads = res.PerTxAccountReads + prefetchAccountReads + balAccountReads
-	stats.StorageReads = res.PerTxStorageReads + prefetchStorageReads + balStorageReads
-	stats.CodeReads = res.PerTxCodeReads
+	stats.AccountReads = res.Reads.Account + prefetchAccountReads + balAccountReads
+	stats.StorageReads = res.Reads.Storage + prefetchStorageReads + balStorageReads
+	stats.CodeReads = res.Reads.Code
 
 	// Cache stats from the shared prefetch reader (accumulates centrally).
 	if r, ok := prefetchReader.(state.ReaderStater); ok {

core/parallel_state_processor.go

@@ -24,14 +24,11 @@ type ProcessResultWithMetrics struct {
 	ExecTime        time.Duration
 	PostProcessTime time.Duration
 	// Counts is the aggregate of per-tx, pre-tx and post-tx state-mutation
-	// counts harvested from each worker statedb. Plain-int snapshot type;
-	// safe to copy.
+	// counts. Plain-int snapshot, safe to copy.
 	Counts state.StateCounts
-	// Per-tx state-read durations summed across parallel workers + pre-tx
-	// + post-tx statedbs. Sum-of-CPU-time semantics; not wall-clock.
-	PerTxAccountReads time.Duration
-	PerTxStorageReads time.Duration
-	PerTxCodeReads    time.Duration
+	// Reads is the aggregate of per-tx, pre-tx and post-tx state-read times.
+	// Sum-of-CPU-time, not wall-clock.
+	Reads state.ReadDurations
 }
 
 // ParallelStateProcessor is used to execute and verify blocks containing
@@ -80,7 +77,7 @@ func validateStateAccesses(lastIdx int, accessList bal.AccessListReader, localAc
 // performs post-tx state transition (system contracts and withdrawals)
 // and calculates the ProcessResult, returning it to be sent on resCh
 // by resultHandler
-func (p *ParallelStateProcessor) prepareExecResult(block *types.Block, tExecStart time.Time, accesses bal.StateAccesses, statedb *state.StateDB, prefetchReader state.Reader, results []txExecResult, aggCounts state.StateCounts, aggAccountReads, aggStorageReads, aggCodeReads time.Duration) *ProcessResultWithMetrics {
+func (p *ParallelStateProcessor) prepareExecResult(block *types.Block, tExecStart time.Time, accesses bal.StateAccesses, statedb *state.StateDB, prefetchReader state.Reader, results []txExecResult, aggCounts state.StateCounts, aggReads state.ReadDurations) *ProcessResultWithMetrics {
 	tExec := time.Since(tExecStart)
 	var requests [][]byte
 	tPostprocessStart := time.Now()
@@ -179,17 +176,11 @@ func (p *ParallelStateProcessor) prepareExecResult(block *types.Block, tExecStar
 
 	tPostprocess := time.Since(tPostprocessStart)
 
-	// Fold post-tx statedb counts into the aggregate. postTxState is local and
-	// would otherwise be discarded; this captures system-contract reads and
-	// the engine.Finalize state mutations.
-	postTxCounts := postTxState.SnapshotCounts()
-	aggCounts.Add(postTxCounts)
-
-	// Fold post-tx statedb reads into the aggregate (system contracts,
-	// withdrawal queue, consolidation queue).
-	aggAccountReads += postTxState.AccountReads
-	aggStorageReads += postTxState.StorageReads
-	aggCodeReads += postTxState.CodeReads
+	// Fold post-tx statedb counts and reads into the aggregate. postTxState is
+	// local and would otherwise be discarded; this captures system-contract
+	// reads (withdrawal queue, consolidation queue) and engine.Finalize.
+	aggCounts.Add(postTxState.SnapshotCounts())
+	aggReads.Add(postTxState.SnapshotReads())
 
 	return &ProcessResultWithMetrics{
 		ProcessResult: &ProcessResult{
@@ -198,12 +189,10 @@ func (p *ParallelStateProcessor) prepareExecResult(block *types.Block, tExecStar
 			Logs:     allLogs,
 			GasUsed:  blockGasUsed,
 		},
-		PostProcessTime:   tPostprocess,
-		ExecTime:          tExec,
-		Counts:            aggCounts,
-		PerTxAccountReads: aggAccountReads,
-		PerTxStorageReads: aggStorageReads,
-		PerTxCodeReads:    aggCodeReads,
+		PostProcessTime: tPostprocess,
+		ExecTime:        tExec,
+		Counts:          aggCounts,
+		Reads:           aggReads,
 	}
 }
 
@@ -220,20 +209,16 @@ type txExecResult struct {
 
 	stateReads bal.StateAccesses
 
-	// Per-tx state-mutation counts, snapshotted from this tx's worker
-	// statedb just before send. Aggregated single-threaded in resultHandler.
+	// Per-tx state-mutation counts and read durations, snapshotted from the
+	// worker statedb just before send. Aggregated single-threaded in
+	// resultHandler.
 	counts state.StateCounts
-
-	// Per-tx state-read durations (auto-populated on the per-tx StateDB during
-	// execution; snapshot before the worker discards the statedb).
-	accountReads time.Duration
-	storageReads time.Duration
-	codeReads    time.Duration
+	reads  state.ReadDurations
 }
 
 // resultHandler polls until all transactions have finished executing and the
 // state root calculation is complete. The result is emitted on resCh.
-func (p *ParallelStateProcessor) resultHandler(block *types.Block, preTxReads bal.StateAccesses, preCounts state.StateCounts, preAR, preSR, preCR time.Duration, statedb *state.StateDB, prefetchReader state.Reader, tExecStart time.Time, txResCh <-chan txExecResult, stateRootCalcResCh <-chan stateRootCalculationResult, resCh chan *ProcessResultWithMetrics) {
+func (p *ParallelStateProcessor) resultHandler(block *types.Block, preTxAccesses bal.StateAccesses, preCounts state.StateCounts, preReads state.ReadDurations, statedb *state.StateDB, prefetchReader state.Reader, tExecStart time.Time, txResCh <-chan txExecResult, stateRootCalcResCh <-chan stateRootCalculationResult, resCh chan *ProcessResultWithMetrics) {
 	// 1. if the block has transactions, receive the execution results from all of them and return an error on resCh if any txs err'd
 	// 2. once all txs are executed, compute the post-tx state transition and produce the ProcessResult sending it on resCh (or an error if the post-tx state didn't match what is reported in the BAL)
 	var results []txExecResult
@@ -241,15 +226,11 @@ func (p *ParallelStateProcessor) resultHandler(block *types.Block, preTxReads ba
 	var execErr error
 	var numTxComplete int
 
-	accesses := preTxReads
-	// aggCounts seeds with the pre-tx contribution (BeaconRoot, ParentBlockHash);
-	// per-tx counts are folded in below; post-tx is folded in prepareExecResult.
+	// Seed aggregates with the pre-tx contribution (BeaconRoot, ParentBlockHash).
+	// Per-tx fold below; post-tx fold in prepareExecResult.
+	accesses := preTxAccesses
 	aggCounts := preCounts
-	// Read durations seeded with pre-tx contribution; per-tx folded in
-	// below; post-tx folded in prepareExecResult.
-	aggAccountReads := preAR
-	aggStorageReads := preSR
-	aggCodeReads := preCR
+	aggReads := preReads
 
 	if len(block.Transactions()) > 0 {
 	loop:
@@ -268,9 +249,7 @@ func (p *ParallelStateProcessor) resultHandler(block *types.Block, preTxReads ba
 						results = append(results, res)
 						accesses.Merge(res.stateReads)
 						aggCounts.Add(res.counts)
-						aggAccountReads += res.accountReads
-						aggStorageReads += res.storageReads
-						aggCodeReads += res.codeReads
+						aggReads.Add(res.reads)
 					}
 				}
 				if numTxComplete == len(block.Transactions()) {
@@ -287,7 +266,7 @@ func (p *ParallelStateProcessor) resultHandler(block *types.Block, preTxReads ba
 		}
 	}
 
-	execResults := p.prepareExecResult(block, tExecStart, accesses, statedb, prefetchReader, results, aggCounts, aggAccountReads, aggStorageReads, aggCodeReads)
+	execResults := p.prepareExecResult(block, tExecStart, accesses, statedb, prefetchReader, results, aggCounts, aggReads)
 	rootCalcRes := <-stateRootCalcResCh
 
 	if execResults.ProcessResult.Error != nil {
@@ -354,21 +333,19 @@ func (p *ParallelStateProcessor) execTx(block *types.Block, tx *types.Transactio
 
 	txRegular, txState := gp.AmsterdamDimensions()
 	return &txExecResult{
-		idx:          balIdx,
-		receipt:      receipt,
-		execGas:      receipt.GasUsed,
-		blockGas:     gp.Used(),
-		txRegular:    txRegular,
-		txState:      txState,
-		stateReads:   db.Reader().(state.StateReaderTracker).GetStateAccessList(),
-		counts:       db.SnapshotCounts(),
-		accountReads: db.AccountReads,
-		storageReads: db.StorageReads,
-		codeReads:    db.CodeReads,
+		idx:        balIdx,
+		receipt:    receipt,
+		execGas:    receipt.GasUsed,
+		blockGas:   gp.Used(),
+		txRegular:  txRegular,
+		txState:    txState,
+		stateReads: db.Reader().(state.StateReaderTracker).GetStateAccessList(),
+		counts:     db.SnapshotCounts(),
+		reads:      db.SnapshotReads(),
 	}
 }
 
-func (p *ParallelStateProcessor) processBlockPreTx(block *types.Block, statedb *state.StateDB, prefetchReader state.Reader, cfg vm.Config) (bal.StateAccesses, state.StateCounts, time.Duration, time.Duration, time.Duration, error) {
+func (p *ParallelStateProcessor) processBlockPreTx(block *types.Block, statedb *state.StateDB, prefetchReader state.Reader, cfg vm.Config) (bal.StateAccesses, state.StateCounts, state.ReadDurations, error) {
 	var (
 		header = block.Header()
 	)
@@ -390,12 +367,12 @@ func (p *ParallelStateProcessor) processBlockPreTx(block *types.Block, statedb *
 	mutations.Merge(pbhMutations)
 	reads := readerWithTracker.(state.StateReaderTracker).GetStateAccessList()
 	if !accessList.MutationsAt(0).Eq(mutations) {
-		return nil, state.StateCounts{}, 0, 0, 0, fmt.Errorf("invalid block access list: mismatch between local/remote access list mutations at idx 0")
+		return nil, state.StateCounts{}, state.ReadDurations{}, fmt.Errorf("invalid block access list: mismatch between local/remote access list mutations at idx 0")
 	}
 	// Snapshot the pre-tx statedb's counts and read-times so system-contract
 	// reads/writes (BeaconRoot, ParentBlockHash) contribute to the aggregate;
 	// sdb is local and would otherwise be discarded.
-	return reads, sdb.SnapshotCounts(), sdb.AccountReads, sdb.StorageReads, sdb.CodeReads, nil
+	return reads, sdb.SnapshotCounts(), sdb.SnapshotReads(), nil
 }
 
 // Process performs EVM execution and state root computation for a block which is known
@@ -415,7 +392,7 @@ func (p *ParallelStateProcessor) Process(block *types.Block, stateTransition *st
 	)
 
 	startingState := statedb.Copy()
-	preReads, preCounts, preAR, preSR, preCR, err := p.processBlockPreTx(block, statedb, balReader, cfg)
+	preTxReads, preCounts, preReads, err := p.processBlockPreTx(block, statedb, balReader, cfg)
 	if err != nil {
 		return nil, err
 	}
@@ -425,7 +402,7 @@ func (p *ParallelStateProcessor) Process(block *types.Block, stateTransition *st
 
 	// execute transactions and state root calculation in parallel
 	tExecStart = time.Now()
-	go p.resultHandler(block, preReads, preCounts, preAR, preSR, preCR, statedb, balReader, tExecStart, txResCh, rootCalcResultCh, resCh)
+	go p.resultHandler(block, preTxReads, preCounts, preReads, statedb, balReader, tExecStart, txResCh, rootCalcResultCh, resCh)
 	var workers errgroup.Group
 	workers.SetLimit(runtime.NumCPU())
 	for i, t := range block.Transactions() {

core/state/state_counts.go

@@ -16,19 +16,28 @@
 
 package state
 
+import "time"
+
+// ReadDurations groups the {Account, Storage, Code} state-read times that are
+// aggregated across pre-tx, per-tx and post-tx statedbs in the BAL parallel
+// path. Sum-of-CPU-time, not wall-clock.
+type ReadDurations struct {
+	Account time.Duration
+	Storage time.Duration
+	Code    time.Duration
+}
+
+// Add merges other into r.
+func (r *ReadDurations) Add(other ReadDurations) {
+	r.Account += other.Account
+	r.Storage += other.Storage
+	r.Code += other.Code
+}
+
 // StateCounts holds count-only statistics gathered during a block's state
-// transition. It is the snapshot/aggregation type: all fields are plain ints,
-// safe to copy and pass by value through channels and struct fields.
-//
-// StateDB still uses atomic counters internally (for concurrent worker
-// updates); the conversion to plain ints happens at the snapshot boundary
-// in (*StateDB).SnapshotCounts. This separation keeps the live atomics
-// scoped to the mutation surface and lets the rest of the pipeline use
-// vet-clean value semantics.
-//
-// Only counts live here — time.Duration fields (AccountReads, StorageReads,
-// etc.) stay on StateDB directly, since their parallel-execution semantics
-// don't fit the simple Add merge pattern.
+// transition. Plain-int snapshot type, safe to copy through channels.
+// Atomic counters on StateDB are converted at the snapshot boundary in
+// SnapshotCounts. Read durations live in ReadDurations (separate type).
 type StateCounts struct {
 	AccountLoaded   int   // accounts retrieved from the database during the state transition
 	AccountUpdated  int   // accounts updated during the state transition

core/state/statedb.go

@@ -241,6 +241,16 @@ func (s *StateDB) SnapshotCounts() StateCounts {
 	}
 }
 
+// SnapshotReads returns a value-copy of the {Account, Storage, Code} read
+// durations accumulated on this StateDB.
+func (s *StateDB) SnapshotReads() ReadDurations {
+	return ReadDurations{
+		Account: s.AccountReads,
+		Storage: s.StorageReads,
+		Code:    s.CodeReads,
+	}
+}
+
 // StartPrefetcher initializes a new trie prefetcher to pull in nodes from the
 // state trie concurrently while the state is mutated so that when we reach the
 // commit phase, most of the needed data is already hot.