From 27dd62eac38dc4265f80a2fa4eaf2635e85035d9 Mon Sep 17 00:00:00 2001
From: Morty <70688412+yiweichi@users.noreply.github.com>
Date: Wed, 3 Dec 2025 21:49:17 +0800
Subject: [PATCH] feat(rollup-relayer): add blob fee tolerance (#1773)

---
 common/version/version.go                        |  2 +-
 rollup/conf/config.json                          |  3 ++-
 rollup/internal/config/relayer.go                |  4 ++++
 rollup/internal/controller/relayer/l2_relayer.go | 12 ++++++++----
 4 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/common/version/version.go b/common/version/version.go
index ba510f3d8..801661cb3 100644
--- a/common/version/version.go
+++ b/common/version/version.go
@@ -5,7 +5,7 @@ import (
 	"runtime/debug"
 )
 
-var tag = "v4.7.9"
+var tag = "v4.7.10"
 
 var commit = func() string {
 	if info, ok := debug.ReadBuildInfo(); ok {
diff --git a/rollup/conf/config.json b/rollup/conf/config.json
index 537ac144b..f4f382022 100644
--- a/rollup/conf/config.json
+++ b/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": 500000000
       },
       "gas_oracle_config": {
         "min_gas_price": 0,
diff --git a/rollup/internal/config/relayer.go b/rollup/internal/config/relayer.go
index 55f6393db..2e50969ad 100644
--- a/rollup/internal/config/relayer.go
+++ b/rollup/internal/config/relayer.go
@@ -48,6 +48,10 @@ type BatchSubmission struct {
 	TimeoutSec int64 `json:"timeout"`
 	// The maximum number of pending batches to keep in the backlog.
 	BacklogMax int64 `json:"backlog_max"`
+	// BlobFeeTolerance 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.
+	BlobFeeTolerance uint64 `json:"blob_fee_tolerance"`
 }
 
 // ChainMonitor this config is used to get batch status from chain_monitor API.
diff --git a/rollup/internal/controller/relayer/l2_relayer.go b/rollup/internal/controller/relayer/l2_relayer.go
index 27cb11543..c3ddbdac4 100644
--- a/rollup/internal/controller/relayer/l2_relayer.go
+++ b/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.BlobFeeTolerance)
+	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),
 		)
 	}