Purely optimistic STM implementations that abort transactions early and don't permit other transactions to read uncommitted data can guarantee forward progress, and I believe that both Haskell's STM and Fraser and Harris's STM do, though I could easily be mistaken about that.
Probably you are right. I vaguely remembered the "Why Transactional Memory Should Not Be Obstruction-Free" paper, but I might have misunderstood or forgotten what it meant (the implementation can be non obstruction-free, but it doesn't mean it can live-lock).
yes, 'synchronize' uses a try_lock/backoff algorithm, same as std::scoped_lock.
edit: it could theoretically livelock, but I believe most if not all STM implementations also do not guarantee forward progress.
Purely optimistic STM implementations that abort transactions early and don't permit other transactions to read uncommitted data can guarantee forward progress, and I believe that both Haskell's STM and Fraser and Harris's STM do, though I could easily be mistaken about that.
Probably you are right. I vaguely remembered the "Why Transactional Memory Should Not Be Obstruction-Free" paper, but I might have misunderstood or forgotten what it meant (the implementation can be non obstruction-free, but it doesn't mean it can live-lock).
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