Skip to content

Improve sequencer surplus calculation #4384

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
joshuacolvin0 wants to merge 2 commits into from
+7 −0
Closed

Improve sequencer surplus calculation #4384

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
befb77c
Fix expected surplus in sequencer
alexandrosfilios Nov 20, 2025
db9b676
Add comment to explain the calculation rationale
alexandrosfilios Feb 9, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
7 changes: 7 additions & 0 deletions execution/gethexec/sequencer.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1553,6 +1553,12 @@ func (s *Sequencer) updateExpectedSurplus(ctx context.Context) (int64, error) {
return 0, fmt.Errorf("error encountered getting blob base fee while updating expectedSurplus: %w", err)
}

// We want to calculate the following two values:
// - l1GasPrice = (blobFeePerByte * blobTxBlobGasPerBlob) / (usableBytesInBlob * 16)
// - backlogCost = backlogCallDataUnits * (blobFeePerByte * blobTxBlobGasPerBlob) / (usableBytesInBlob * 16)
// If we divide by usableBytesInBlob too early, the value of blobFeePerByte becomes zero because of rounding.
// Then even if we multiply with backlogCallDataUnits, the value will still remain zero.
// This is why we multiply with backlogCallDataUnits before we divide.
if backlogCallDataUnits == 0 {
blobFeePerByte.Mul(blobFeePerByte, blobTxBlobGasPerBlob)
blobFeePerByte.Div(blobFeePerByte, usableBytesInBlob)
Expand All @@ -1561,6 +1567,7 @@ func (s *Sequencer) updateExpectedSurplus(ctx context.Context) (int64, error) {
} else {
// l1GasPrice can be zero because of roundings, hence backlogCost is calculated separately
backlogFee := big.NewInt(backlogCallDataUnits)
backlogFee.Mul(backlogFee, blobFeePerByte)
backlogFee.Mul(backlogFee, blobTxBlobGasPerBlob)
backlogFee.Div(backlogFee, usableBytesInBlob)
backlogCost = backlogFee.Int64() / 16
Expand Down
Loading