feat(app): record app_block_gas_used per finalized block

app/app.go

@@ -1327,7 +1327,7 @@ func (app *App) FinalizeBlocker(ctx sdk.Context, req *abci.RequestFinalizeBlock)
 			cms := app.WriteState()
 			app.LightInvarianceChecks(ctx.Context(), cms, app.lightInvarianceConfig)
 			appHash := app.GetWorkingHash()
-			resp := app.getFinalizeBlockResponse(appHash, events, txRes, endBlockResp, consensusParamUpdates)
+			resp := app.getFinalizeBlockResponse(ctx.Context(), appHash, events, txRes, endBlockResp, consensusParamUpdates)
 			if hasHeadNotifier {
 				headNotifier.Stash(req, &resp)
 			}
@@ -1357,7 +1357,7 @@ func (app *App) FinalizeBlocker(ctx sdk.Context, req *abci.RequestFinalizeBlock)
 	cms := app.WriteState()
 	app.LightInvarianceChecks(ctx.Context(), cms, app.lightInvarianceConfig)
 	appHash := app.GetWorkingHash()
-	resp := app.getFinalizeBlockResponse(appHash, events, txResults, endBlockResp, consensusParamUpdates)
+	resp := app.getFinalizeBlockResponse(ctx.Context(), appHash, events, txResults, endBlockResp, consensusParamUpdates)
 	if hasHeadNotifier {
 		headNotifier.Stash(req, &resp)
 	}
@@ -2318,6 +2318,7 @@ func (app *App) DecodeTransactionsConcurrently(ctx sdk.Context, txs [][]byte) []
 }
 
 func (app *App) getFinalizeBlockResponse(
+	ctx context.Context,
 	appHash []byte,
 	events []abci.Event,
 	txResults []*abci.ExecTxResult,
@@ -2327,6 +2328,14 @@ func (app *App) getFinalizeBlockResponse(
 	if app.EvmKeeper.EthReplayConfig.Enabled || app.EvmKeeper.EthBlockTestConfig.Enabled {
 		return abci.ResponseFinalizeBlock{}
 	}
+
+	// Both FinalizeBlocker paths that build a response converge here, so this records once
+	// per finalized block; ProcessBlock runs twice for a height whose optimistic result is
+	// discarded.
+	if gasUsed, ok := sumBlockGasUsed(txResults); ok {
+		appMetrics.blockGasUsed.Record(ctx, gasUsed)
+	}
+
 	return abci.ResponseFinalizeBlock{
 		Events:    events,
 		TxResults: txResults,
@@ -2341,6 +2350,24 @@ func (app *App) getFinalizeBlockResponse(
 	}
 }
 
+// sumBlockGasUsed totals the gas consumed by every non-nil transaction result in a block.
+// It reports false when a result carries negative gas or when the total overflows int64;
+// the total is then meaningless and callers must discard it.
+func sumBlockGasUsed(txResults []*abci.ExecTxResult) (int64, bool) {
+	var total int64
+	for _, txResult := range txResults {
+		if txResult == nil {
+			continue
+		}
+		gasUsed := txResult.GasUsed
+		if gasUsed < 0 || total > math.MaxInt64-gasUsed {
+			return 0, false
+		}
+		total += gasUsed
+	}
+	return total, true
+}
+
 func cloneConsensusParams(params *tmproto.ConsensusParams) *tmproto.ConsensusParams {
 	if params == nil {
 		return nil

app/block_gas_used_test.go

@@ -0,0 +1,61 @@
+package app
+
+import (
+	"math"
+	"testing"
+
+	"github.com/sei-protocol/sei-chain/sei-tendermint/abci/types"
+	"github.com/stretchr/testify/require"
+)
+
+// gasUsedResults builds one ExecTxResult per gas value, matching the shape
+// FinalizeBlock hands to sumBlockGasUsed.
+func gasUsedResults(gasUsed ...int64) []*types.ExecTxResult {
+	results := make([]*types.ExecTxResult, 0, len(gasUsed))
+	for _, g := range gasUsed {
+		results = append(results, &types.ExecTxResult{GasUsed: g})
+	}
+	return results
+}
+
+// TestSumBlockGasUsedEmptyBlock records a zero total for a block with no transactions, so
+// the histogram carries one sample per finalized block.
+func TestSumBlockGasUsedEmptyBlock(t *testing.T) {
+	total, ok := sumBlockGasUsed(nil)
+	require.True(t, ok)
+	require.Zero(t, total)
+}
+
+// TestSumBlockGasUsedSumsResults covers the ordinary path.
+func TestSumBlockGasUsedSumsResults(t *testing.T) {
+	total, ok := sumBlockGasUsed(gasUsedResults(21_000, 100_000, 0, 5_000_000))
+	require.True(t, ok)
+	require.Equal(t, int64(5_121_000), total)
+}
+
+// TestSumBlockGasUsedSkipsNilResults exercises the nil-entry branch of the accounting loop.
+func TestSumBlockGasUsedSkipsNilResults(t *testing.T) {
+	results := []*types.ExecTxResult{nil, {GasUsed: 21_000}, nil, {GasUsed: 42_000}}
+	total, ok := sumBlockGasUsed(results)
+	require.True(t, ok)
+	require.Equal(t, int64(63_000), total)
+}
+
+// TestSumBlockGasUsedRejectsNegativeGas exercises the negative-gas branch.
+func TestSumBlockGasUsedRejectsNegativeGas(t *testing.T) {
+	_, ok := sumBlockGasUsed(gasUsedResults(21_000, -1))
+	require.False(t, ok)
+}
+
+// TestSumBlockGasUsedRejectsOverflow exercises the int64 overflow branch.
+func TestSumBlockGasUsedRejectsOverflow(t *testing.T) {
+	_, ok := sumBlockGasUsed(gasUsedResults(math.MaxInt64, 1))
+	require.False(t, ok)
+}
+
+// TestSumBlockGasUsedAcceptsExactInt64Max confirms the overflow guard is not off by one.
+func TestSumBlockGasUsedAcceptsExactInt64Max(t *testing.T) {
+	total, ok := sumBlockGasUsed(gasUsedResults(math.MaxInt64-1, 1))
+	require.True(t, ok)
+	require.Equal(t, int64(math.MaxInt64), total)
+}

app/consensus_params_test.go

@@ -56,6 +56,7 @@ func TestGetFinalizeBlockResponsePropagatesFullConsensusParams(t *testing.T) {
 
 	app := &App{}
 	resp := app.getFinalizeBlockResponse(
+		t.Context(),
 		[]byte("hash"),
 		nil,
 		nil,

app/metrics.go

@@ -25,7 +25,9 @@ var (
 		0.000025, 0.000050, 0.0001, 0.0005, 0.001, 0.0025, 0.005, 0.010, 0.020, 0.050, 0.075, 0.1, 0.25, 0.5, 1, 10,
 	)
 
-	// blockGasWantedBuckets covers the 0–50 M gas range (current MaxGasWanted cap)
+	// blockGasWantedBuckets covers the 0–50 M gas range (current MaxGasWanted cap).
+	// The per-block gas wanted and gas used histograms share it: a transaction's gas
+	// used is bounded by its gas wanted, so the same cap bounds both block totals.
 	blockGasWantedBuckets = metric.WithExplicitBucketBoundaries(
 		10e3, 25e3, 50e3, 100e3, 250e3, 500e3,
 		1e6, 2.5e6, 5e6, 10e6, 12.5e6, 25e6, 50e6,
@@ -66,6 +68,7 @@ var (
 		// Per-block gas utilisation
 		blockGasWanted      metric.Int64Histogram
 		blockGasWantedRatio metric.Float64Histogram
+		blockGasUsed        metric.Int64Histogram
 
 		// Light invariance check
 		invarianceDuration      metric.Float64Histogram
@@ -180,6 +183,16 @@ var (
 			blockGasWantedRatioBuckets,
 		)),
 
+		blockGasUsed: must(meter.Int64Histogram(
+			"app_block_gas_used",
+			metric.WithDescription("Per-block total gas used across all transactions. Recorded on "+
+				"FinalizeBlock, so unlike app_block_gas_wanted (recorded on ProcessProposal) it has "+
+				"samples during block/state sync with no matching gas_wanted sample -- do not divide "+
+				"the two without accounting for that"),
+			metric.WithUnit("{gas}"),
+			blockGasWantedBuckets,
+		)),
+
 		invarianceDuration: must(meter.Float64Histogram(
 			"app_lightinvariance_supply_duration",
 			metric.WithDescription("Duration of light invariance total supply check"),