feat(rollup-relayer): add blob fee tolerance

Author: yiweichi

rollup/conf/config.json

@@ -58,7 +58,8 @@
         "min_batches": 1,
         "max_batches": 6,
         "timeout": 7200,
-        "backlog_max": 75
+        "backlog_max": 75,
+        "blob_fee_tolerance_wei": 10000000000
       },
       "gas_oracle_config": {
         "min_gas_price": 0,

rollup/internal/config/relayer.go

@@ -48,6 +48,11 @@ type BatchSubmission struct {
 	TimeoutSec int64 `json:"timeout"`
 	// The maximum number of pending batches to keep in the backlog.
 	BacklogMax int64 `json:"backlog_max"`
+	// BlobFeeToleranceWei is the absolute tolerance (in wei) added to the target blob fee.
+	// If the current fee is below target + tolerance, we proceed with submission.
+	// This prevents skipping submission when the price difference is negligible (e.g., 1 wei).
+	// Recommended value: 10 gwei (10000000000 wei).
+	BlobFeeToleranceWei uint64 `json:"blob_fee_tolerance_wei"`
 }
 
 // ChainMonitor this config is used to get batch status from chain_monitor API.

rollup/internal/controller/relayer/l2_relayer.go

@@ -1255,16 +1255,20 @@ func (r *Layer2Relayer) skipSubmitByFee(oldest time.Time, metrics *l2RelayerMetr
 	target := calculateTargetPrice(windowSec, r.batchStrategy, oldest, hist)
 	current := hist[len(hist)-1]
 
+	// apply absolute tolerance offset to target
+	tolerance := new(big.Int).SetUint64(r.cfg.BatchSubmission.BlobFeeToleranceWei)
+	threshold := new(big.Int).Add(target, tolerance)
+
 	currentFloat, _ := current.Float64()
 	targetFloat, _ := target.Float64()
 	metrics.rollupL2RelayerCurrentBlobPrice.Set(currentFloat)
 	metrics.rollupL2RelayerTargetBlobPrice.Set(targetFloat)
 
-	// if current fee > target and still inside the timeout window, skip
-	if current.Cmp(target) > 0 && time.Since(oldest) < time.Duration(windowSec)*time.Second {
+	// if current fee > threshold (target + tolerance) and still inside the timeout window, skip
+	if current.Cmp(threshold) > 0 && time.Since(oldest) < time.Duration(windowSec)*time.Second {
 		return true, fmt.Errorf(
-			"blob-fee above target & window not yet passed; current=%s target=%s age=%s",
-			current.String(), target.String(), time.Since(oldest),
+			"blob-fee above threshold & window not yet passed; current=%s target=%s threshold=%s tolerance=%s age=%s",
+			current.String(), target.String(), threshold.String(), tolerance.String(), time.Since(oldest),
 		)
 	}