Key PseudorandomNumberGenerator by thread name to survive CPU thread recreation#212
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Key PseudorandomNumberGenerator by thread name to survive CPU thread recreation#212mananni-silabs wants to merge 1 commit into
mananni-silabs wants to merge 1 commit into
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…recreation The generator is ThreadLocal and seeds each thread's Random solely from the thread name (name.Sum() ^ baseSeed). ThreadLocal, however, keys by the physical managed thread. CPU cores that halt and resume (e.g. a power-managed radio sequencer) have their dispatcher thread torn down on halt and recreated under the same name on resume, so each recreation built a fresh Random with an identical seed and restarted the pseudo-random stream from the beginning. Cache RandomGenerator instances by logical thread name so a thread recreated under the same name continues its existing, deterministic stream, and clear the cache in ResetSeed. Determinism is preserved because the recreation count is itself deterministic for a given seed.
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The generator is ThreadLocal and seeds each thread's Random solely from the thread name (name.Sum() ^ baseSeed). ThreadLocal, however, keys by the physical managed thread. CPU cores that halt and resume (e.g. a power-managed radio sequencer) have their dispatcher thread torn down on halt and recreated under the same name on resume, so each recreation built a fresh Random with an identical seed and restarted the pseudo-random stream from the beginning.
Cache RandomGenerator instances by logical thread name so a thread recreated under the same name continues its existing, deterministic stream, and clear the cache in ResetSeed. Determinism is preserved because the recreation count is itself deterministic for a given seed.