rewrite of sei-load generator and sender.

[pompon0]

Primary reason for the rewrite is support for non-happy paths for autobahn loadtesting - rejected transactions/not successfully executed/etc. The idea is that if sending a tx fails, we need to check the account nonce before sending the next transaction. Note that this affects only accounts from the long-lived pools - accounts generated for the sake of sending just 1 transaction (aka "new accounts") do not benefit from this extra logic.

The nonces, as well as the txs waiting to be sent are managed by TxsQueue, which ensures that:

• inserted (generated) transactions have expected nonces
• transactions per account are sent sequentially (otherwise they will be rejected by autobahn)

TxsQueue is managed by ShardedSender.

Additionally

• removed unnecessary abstractions in both sender and generator logic
• made Generator.Run accept the sender which exposes Nonce(), Flush() and Send() calls
• added Generator <-> Sender integration tests
• removed open/closed loop logic (might need to be reintroduced later if needed)
• removed utils/rng in favor of just using a single Rand synchronously (we don't have other use cases). If concurrent Rand usage is needed, a SplitRng method was introduced (slower but robust alternative to SplitMix).

[cursor]

PR Summary

High Risk
Large refactor of transaction generation, nonce sequencing, and send failure handling on the critical load-test path; open-loop arrival scheduling was removed, which may change benchmark behavior.

Overview
Rewrites the generator and sender so load tests can recover when sends fail (e.g. Autobahn rejects txs). Tracked pool accounts get nonce sync from chain on failure; untracked one-shot accounts skip that.

Sender: Replaces per-shard worker queues with a TxsQueue (bounded by MaxInFlight) that enforces per-address nonce order and sequential sends. ShardedSender pushes into the queue, pops ready txs, and on RPC failure for tracked senders calls Reset(addr, chain nonce) after eth_getTransactionCount. ethClient dials all endpoints and shards by sender address; sends are synchronous from the sender loop (no per-endpoint request channels).

Generator: Drops the dispatcher, weighted generator, utils/rng sub-streams, and open/closed-loop scheduling. NewGenerator(rng, cfg) builds scenarios; Run(ctx, rng, txSender) loops scenarios, asks txSender.Nonce(sender), and Send. Prewarm is Generator.Prewarm. Gas/distribution pickers take an explicit *rand.Rand at draw time.

main: Wires generator directly to the sender background task; run summary no longer reports open-loop drops.

Config: Settings.Validate now only requires MaxInFlight > 0 (arrival-model checks removed).

Adds generator↔sender integration tests (nonce rewinds, mixed tracked/untracked pools).

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[cursor]

Dropped txs look successful

Medium Severity

When TxsQueue.Push rejects a transaction for a nonce mismatch, it logs and returns nil. Generator.Run treats that as a successful send and immediately builds another transaction, which can spin at full speed without making progress until context cancel if the queue and generator stay desynchronized.

Additional Locations (1)

• generator/generator.go#L195-L198

 

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[pompon0]

WAI

[cursor]

Buffer size no longer bounds queue

Medium Severity

NewShardedSender sizes TxsQueue only from Settings.MaxInFlight. Settings.BufferSize and LoadConfig.TotalQueueSize() are no longer used, so existing configs that tune bufferSize/--buffer-size do not limit queue depth or memory as before.

 

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[cursor]

Worker queue metric disabled

Low Severity

The worker_queue_length observable gauge callback no longer records observations: the ShardStats loop is commented out and only assigns _ = ss. Scrapers always see an empty series after the sender rewrite removed per-shard queues.

 

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[cursor]

Stale nonce before async send

Medium Severity

Run reads txSender.Nonce, builds and signs the tx, then calls Send without holding sender/queue state. A concurrent send failure and Reset can advance the queue nonce before Push, producing signed txs the queue rejects.

 

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[pompon0]

Rejection is silent and it is expected, since we send the txs asynchronously.

[cursor]

Workers setting no longer applied

Medium Severity

The send path now runs a single ShardedSender background task and no longer uses Settings.TasksPerEndpoint (workers) or LoadConfig.GetNumShards, even though those settings remain in config, CLI, and tests. Raising --workers does not increase RPC parallelism as documented.

 

^{Reviewed by Cursor Bugbot for commit a28e7c0. Configure here.}

[cursor]

Deploy nonces skip unused slots

High Severity

Sequential scenario deployment passes the scenario list index as the deployer nonce. Instances that do not broadcast a deployment transaction still advance that index, so the next contract deployment can be signed with a nonce above the account’s on-chain nonce and be rejected.

 

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[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

There are 7 total unresolved issues (including 6 from previous reviews).

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[cursor]

Workers setting no longer applied

Medium Severity

Settings.TasksPerEndpoint / --workers no longer scale send parallelism: ShardedSender.Run uses one rate-limited pop/send loop and ethClient dials endpoints without per-worker tasks, while main.go still logs total tasks from workers × endpoints.

 

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