feat(search): Simple multi-reader multi-writer mutex for hnsw index #6156
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| vector<pair<float, GlobalDocId>> Knn(float* target, size_t k, std::optional<size_t> ef) { | ||
| world_.setEf(ef.value_or(kDefaultEfRuntime)); |
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Consider moving the world_.setEf(...) call inside the MRMWMutexLock scope; setEf mutates shared state and, as written, can race with concurrent reads/writes. (Also applies to the filtered Knn overload below.)
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romange
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Dec 3, 2025
romange
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Dec 3, 2025
| return mode == LockMode::kReadLock ? LockMode::kWriteLock : LockMode::kReadLock; | ||
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| util::fb2::Mutex mutex_; |
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nit: you also contend on mutex_, though here maybe absl::SpinLock would fit better as you take it for a small period of time. you could use CondVarAny to be able to use locks with a different type.
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not the most important thing though.
romange
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Dec 3, 2025
romange
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Dec 3, 2025
kostasrim
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Dec 3, 2025
Implementation of multi-reader multi-writer mutex that supports concurrent writes or reads but not a mix of reads and writes in same time. Unit test for testing MRMWMutex class. Signed-off-by: mkaruza <mario@dragonflydb.io>
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Implementation of multi-reader multi-writer mutex that supports concurrent writes or reads but not a mix of reads and writes in same time.
Unit test for testing MRMWMutex class.