Sei Hermes Ahead of Giga: What the 68ms Result Actually Means
Sei Labs (
@Sei_Labs) released laboratory results for Hermes, the consensus protocol Sei Labs plans to deploy on
@SeiNetwork's upcoming Sei Giga upgrade.
The key metric is 68 ms of median finality at 100,000 tx/s.
The 68 ms is a lab result, not current mainnet performance.
But it is the clearest we've had to date on how Sei envisions Giga performing with a fast leader and without one.
So let's look at what that means, and what it doesn't mean.
(1) What Hermes is
Hermes is a partially synchronous consensus algorithm designed for Sei Giga.
It keeps the speed of the most efficient leader-based consensus algorithms but adds a fallback that prevents finalization from being blocked if the leader is slow or unavailable.
It builds on Autobahn, the data availability layer specified for Giga. Autobahn distributes transaction data across lanes per validator, and Hermes orders it by finalizing a common history of lane tips.
(2) The Numbers...
Under the no-fault test, Sei Labs processed 51 validators across four regions with a stable load of 100,000 transactions per second.
The median finality was 68 ms. 95th percentile was 101 ms.
In the same test run, Hermes overlapped Minimmit from the 1st to the 99th percentile.
(3) The number that actually counts counts
Sei Labs stalled three successive leaders and measured their tail latency:
- Hermes: median 104ms, p95 206ms
- Minimmit: median 125ms, p95 365ms
- Autobahn: median 141ms, p95 386ms
- Ambulance: median 241ms, p95 664ms
Hermes reduced p95 by 44% vs. Minimmit, 47% vs. Autobahn, and 69% vs. Ambulance. Hermes' own p95 increased by 2.2x from the baseline. Other protocols' p95 increased by 3.5x to 5.8x.
(4) Where this sits on the Giga Roadmap
The Giga whitepaper for June 2026 reports more than 5 gigagas per second and sub-250ms ordering finality on an internal devnet of 40 nodes spread out across 20 regions.
The 200,000 TPS goal for the public testnet associated with Autobahn is 400 ms finality. Giga is intended as in-place updates to the running Sei chain, not a separate network.
Hermes is the next level of consensus after that. The 68ms figure, if it has survived widespread implementation, is contained within the sub-250ms ordering target.
(5) What the test doesn’t reveal
The fast run consisted of four European geographic areas, not a globally distributed validator set.
Sei Labs performed the fault tolerance analysis on committees designed to tolerate three faults, not as a statement about the current mainnet validator geographic distribution.
Mainnet performance will also rely on execution, storage, and network as well as consensus capabilities. Finality of ordering is different than a user getting a state receipt.
Thus, the proper context here is limited. Hermes is Sei’s solution to maintaining the two-delay fast path and preventing a slow leader from exploding the tail.
In the lab, this worked as expected: 68 ms median, 101 ms p95 when all leaders were healthy, and 206 ms p95 when three were faulty.
Will this pattern survive in the Giga public testnet?