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3 posts tagged with "StereumLabs AI"

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Tracing a Besu memory leak to a one-line method

· 9 min read
Stefan Kobrc
Founder RockLogic
StereumLabs AI
Artificial Intelligence

Six Besu nodes, same version, same hardware, same config. Five held a flat JVM heap around 1.0 to 1.3 GB. The sixth climbed about 10 GB a day and was on track to be OOM-killed roughly 30 hours after a restart. The one thing different about it was the consensus client on the other side of the engine API.

This is a walkthrough of how StereumLabs AI, reading our fleet's metrics and logs, took that one anomalous node, traced it to a single method, and filed it upstream. Besu shipped a round of mitigations and closed the issue. A later devnet reproduction showed the underlying layers still pile up, the issue was reopened, and the fix that followed is now in review. The bug is operational: recoverable by a restart, no consensus impact, no double-sign, no state-root divergence. It is also the kind of cross-client interaction a single-node test will never surface, because it only appears when a live pairing lands in a specific state.

Six identical Besu nodes over time: five hold a flat JVM heap near 1 GB while the Prysm-paired node climbs about 10 GB per day toward an out-of-memory kill

StereumLabs introduced: the stack behind our Ethereum client measurements

· 21 min read
Stefan Kobrc
Founder RockLogic
StereumLabs AI
Artificial Intelligence

Ethereum runs on two layers: an execution client (EC) handles the EVM, transactions, and world state, and a consensus client (CC) handles Proof-of-Stake fork choice and validator duties. Six EC implementations and seven CC implementations exist in production today, paired in dozens of combinations across the network. StereumLabs runs all of them, side by side, on identical hardware in our Vienna data center, and publishes the numbers.

This post is the technical introduction to that platform: the bare-metal fleet, the metrics and logs pipeline, the label conventions that make the pairings comparable, and the in-house AI workflow that turns the resulting telemetry into the blog posts you are reading.

RockLogic publishes a separate case study on the business side of this workflow: how the same "AI on own data" pattern keeps customer telemetry inside the perimeter while still producing useful answers. This post is the technical view from the other side of the same workflow.

Inside the StereumLabs stack: how we measure Ethereum clients from bare metal up