[Corpus] Use threads for datastore operations under targets feature flag - #5352
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LGTM! Thanks for catching and fixing this. Nice job!
PauloVLB
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b/530149063
Possible Problem
corpus_pruningtasks are failing silently with OOM because of how we do GCS operations (uploads, deletions). We are using a process pool with 16 workers, which callsfork(). If the parent process memory is large, doing this multiplies the memory and kills the bot instantly.Proposed Solution
Switch from processes to threads for these I/O bound GCS operations in
storage.py. Threads share memory, avoiding thefork()memory multiplication.To roll this out safely, it is guarded by the
STORAGE_THREADED_OPS_FUZZ_TARGETSfeature flag.Feature Flag Setup
Testing
We are going to test this with the
iperfproject, which is a known project where we can test on. Specifically, we will addlibFuzzer_iperf_cjson_fuzzto the feature flag allowlist.Validation
I validated this in the
devenvironment and verified that the code path is triggered correctly and works as expected.