Add epoch interruption to WASM engine for cooperative yielding #32806
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Jun 16, 2025
| // Need to do this on some non-async thread to make sure it makes progress regardless | ||
| // of if extensions are blocking. | ||
| let engine_ref = engine.weak(); | ||
| thread::spawn(move || { |
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let me know if there is a more "zed" way of having a way to do work outside the executor.
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The background executor can run many tasks in parallel, so it should be fine to rely on that (unless I'm missing something)?
Though this also seems ok
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The idea is to have the epoch incrementing happen outside the executor, because otherwise, if all your threads are somehow blocked, then the epoch isn't incremented and then the tasks never yield
Prevent extensions from blocking async threads by enabling epoch interruption with 100ms intervals. Extensions will yield control back to the executor regularly during Future::poll operations. Addresses the [discussion](#24515) that goes into depth on why this is important when enabling async support with Wasmtime.
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Switches from spawning a dedicated thread to using a Timer task for WASM engine epoch interruption, avoiding unnecessary thread overhead while maintaining the same functionality.
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Prevent extensions from blocking async threads by enabling epoch
interruption with 100ms intervals. Extensions will yield control back to
the executor regularly during Future::poll operations.
Addresses the
discussion
that goes into depth on why this is important when enabling async
support with Wasmtime.
Release Notes: