Add a backpressure-aware export streaming chunk-size and memory-ceiling benchmark in src/tests/performance/exportStream.perf.test.ts

[1nonlypiece]

📌 Description

The bulk export pipeline streams NDJSON/gzip, but there is no benchmark
asserting it holds a bounded memory ceiling under backpressure (a slow
client) and that chunk sizing is tuned for throughput. An unbounded buffer here
would let one large export OOM the process.

This issue adds a streaming benchmark asserting bounded memory under
backpressure and measuring throughput across chunk sizes.

Goal: prove export streaming stays within a memory ceiling under a slow
consumer and document the throughput-optimal chunk size.

🎯 Requirements and Context

• Must simulate a slow consumer and assert peak memory stays bounded.
• Must measure throughput across chunk sizes and record the chosen value.
• Must verify gzip and NDJSON framing remain correct under chunking.
• Must run with bun test.

🛠️ Suggested Execution

1. Fork the repo and create a branch

git checkout -b perf/export-stream-backpressure

2. Implement changes

• Add src/tests/performance/exportStream.perf.test.ts exercising
  src/services/exportQueue.ts/src/routes/exports.ts.
• Document the chunk-size choice in docs/exports.md.

3. Test and commit

• Run with bun test.
• Cover edge cases: slow consumer memory ceiling, large dataset, gzip framing,
  abort mid-stream.

Example commit message

perf: backpressure-aware export streaming memory benchmark

✅ Guidelines

• Minimum 95% test coverage on the new/changed lines.
• Clear, reviewer-friendly documentation.
• No regressions on existing export streaming.
• Timeframe: 96 hours.

🏷️ Labels

type-performance · area-backend · type-testing · MAYBE REWARDED · GRANTFOX OSS · OFFICIAL CAMPAIGN

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[codenerde]

@codenerde has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Good day maintainer, hi,

Please can I work on this project with immediate effect?

Thank you!

ℹ️ Repo Maintainers: To accept this application, review their application or assign @codenerde to this issue.

[drips-wave]

Congratulations, @codenerde! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

🧑‍💻 @codenerde: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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