refactor: replace setTimeout with Atomics.waitAsync #178
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Replace the setTimeout-based polling in wait.js with Atomics.waitAsync for more efficient, event-driven waiting on SharedArrayBuffer state changes. Key changes: - Use Atomics.waitAsync to wait for value changes with notifications - Add 10ms fallback timeout for missed notifications - Add setInterval keepalive in worker.js since waitAsync promises don't keep the Node.js event loop alive 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
Add Atomics.notify(READ_INDEX) after resetting indexes to 0 during buffer wraparound. Without this, the worker would wait for the full timeout when the buffer wrapped around, causing significant performance degradation. Also increase WAIT_MS from 10ms to 1000ms as a fallback poll interval, which is now safe since notifications are properly sent. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
Since notifications are now properly sent after buffer wraparound, the timeout is just a safety fallback. Increase to 10s for better power efficiency when idle. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
The keepalive only needs to prevent worker exit, not run frequently. 1 hour is sufficient and more power-efficient. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
jsumners
approved these changes
Dec 1, 2025
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Summary
lib/wait.jswithAtomics.waitAsyncfor more efficient, event-driven waiting on SharedArrayBuffer state changesAtomics.notify(READ_INDEX)after buffer wraparound to prevent missed notificationssetIntervalkeepalive inlib/worker.jssinceAtomics.waitAsyncpromises don't keep the Node.js event loop aliveBenchmark Results
Test plan
🤖 Generated with Claude Code