Disable GC zeal allocation counter when retrying after GC#13278
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With a GC zeal allocation counter of `1`, we would otherwise indefinitely fail to allocate, even after we did the GC that the counter triggered, when we tried to allocate again the GC zeal counter would force-return another OOM. Instead, we temporarily disable the GC zeal allocation counter in `retry_after_gc_async` on the retry path. This resets the counter after we have done our second-attempt allocation, giving the desired sequence of events for `gc_zeal_alloc_counter=1` where we GC once on every `retry_after_gc_async` call: * Attempt to allocate * Fails with GC OOM due to `gc_zeal_alloc_counter` going from `1` to `0` * `gc_zeal_alloc_counter` reset to `1` * Disable `gc_zeal_alloc_counter` * Do GC-or-growth * Retry allocation * Succeeds or fails without interference from the `gc_zeal_alloc_counter` * Re-enable `gc_zeal_alloc_counter=1` so everything repeats on the next `retry_after_gc_async` call Fixes bytecodealliance#13263
alexcrichton
approved these changes
May 5, 2026
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With a GC zeal allocation counter of
1, we would otherwise indefinitely fail to allocate, even after we did the GC that the counter triggered, when we tried to allocate again the GC zeal counter would force-return another OOM.Instead, we temporarily disable the GC zeal allocation counter in
retry_after_gc_asyncon the retry path. This resets the counter after we have done our second-attempt allocation, giving the desired sequence of events forgc_zeal_alloc_counter=1where we GC once on everyretry_after_gc_asynccall:gc_zeal_alloc_countergoing from1to0gc_zeal_alloc_counterreset to1gc_zeal_alloc_countergc_zeal_alloc_countergc_zeal_alloc_counter=1so everything repeats on the nextretry_after_gc_asynccallFixes #13263