On 9 Jul 2010, at 19:58, Gabor PALI wrote: >> I assume there are reasonable alternatives that work around the >> potential race with a small probability of a missed or extra update, >> or similar, which would be fine. > > In a few words: As far as I know, 64-bit atomic counters could be > implemented by using cmpxchg8b or by a plain uint64_t variable protected > by some kind of locking(9).
If we can do it in one atomic in the common case, and two atomics in an edge case, that sounds fine. I think any use of locking(9) would be sufficiently costly as to not be worth the improvements in consistency, given the frequency of statistics operations. Robert_______________________________________________ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
