fix: ICP-8826: Workaround for allocation issue in wasmtime-java - #202
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wasmtime-java has a leak whenever any linker function is retrieved, thus resulting in a massive leak every iteration when it's fetched as part of the variable evaluation hot path. This adopts the same premise as the C# SDK where storing this reduces, but does not resolve the leak entirely. This minimizes the cost, but it still has a large initial RSS leak that cannot be fixed as each function is initialized/mapped. Due to the EOL of DVC coming - this is the only fix we can reasonably make with acceptable turnarounds.
JamieSinn
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Pull request overview
This PR mitigates native memory growth in the local bucketing path by avoiding repeated WASM export resolution (which leaks native handles in wasmtime-java), shifting export binding to LocalBucketing construction time.
Changes:
- Cache WASM
Funcbindings (viaWasmFunctions.*) asLocalBucketingfields and reuse them across calls. - Add an
export(String name)helper to resolve exports once and fail fast on missing exports. - Update the release workflow commit email used for automated version bumps.
Reviewed changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.
| File | Description |
|---|---|
src/main/java/com/devcycle/sdk/server/local/bucketing/LocalBucketing.java |
Caches WASM function bindings and adds a helper for one-time export resolution to reduce per-call native handle leaks. |
.github/workflows/release.yml |
Updates the git author email used in the release commit step. |
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| * <p>The returned {@link Func} owns a native handle that is only released by | ||
| * {@code Func.dispose()}, so these must not be fetched per call. | ||
| * |
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| * <p>Runtime error behaviour is otherwise unchanged: WASM traps still surface as | ||
| * {@code WasmtimeException} from the calling method, and a trap does not invalidate these | ||
| * bindings. See {@code LocalBucketingErrorHandlingTest}. | ||
| */ |
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jonathannorris
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wasmtime-java has a leak whenever any linker function is retrieved, thus resulting in a massive leak every iteration when it's fetched as part of the variable evaluation hot path.
This adopts the same premise as the C# SDK where storing this reduces, but does not resolve the leak entirely. This minimizes the cost, but it still has a large initial RSS leak that cannot be fixed as each function is initialized/mapped.
Close #195