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* for appends, so can only be removed later when other nodes are |
325 |
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* appended. (2) We cannot necessarily unlink s given a |
326 |
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* predecessor node that is matched (including the case of being |
327 |
< |
* cancelled): the predecessor may already be already unspliced, |
328 |
< |
* in which case some previous reachable node may still point to |
329 |
< |
* s. (For further explanation see Herlihy & Shavit "The Art of |
327 |
> |
* cancelled): the predecessor may already be unspliced, in which |
328 |
> |
* case some previous reachable node may still point to s. |
329 |
> |
* (For further explanation see Herlihy & Shavit "The Art of |
330 |
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* Multiprocessor Programming" chapter 9). Although, in both |
331 |
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* cases, we can rule out the need for further action if either s |
332 |
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* or its predecessor are (or can be made to be) at, or fall off |
359 |
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* Because the sweepVotes estimate is conservative, and because |
360 |
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* nodes become unlinked "naturally" as they fall off the head of |
361 |
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* the queue, and because we allow votes to accumulate even while |
362 |
< |
* sweeps are in progress, there are typically signficantly fewer |
362 |
> |
* sweeps are in progress, there are typically significantly fewer |
363 |
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* such nodes than estimated. Choice of a threshold value |
364 |
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* balances the likelihood of wasted effort and contention, versus |
365 |
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* providing a worst-case bound on retention of interior nodes in |