Subj : Re: posix and lock-free algorithms To : comp.programming.threads From : David Hopwood Date : Sat Aug 13 2005 01:56 am Joe Seigh wrote: > David Schwartz, sensing the danger he's in, further qualifies his argument: > >> "Joe Seigh" wrote: >> >>> I think it would depend on the particular function what "synchronize >>> memory" means. I can think of some implementations where some of the >>> Posix functions would be a no op and allow memory accesses to be reordered >>> by the compiler and or hardware. >> >> I don't think it's at all reasonable to say that a function >> "synchronizes memory" if memory accesses can be reordered around it >> (as seen by another CPU that also uses a function that is required to >> "synchronize memory"). In fact, I find this position totally >> unreasonable. > > "as seen by" huh? :) Right, that's part of it. DS also seems to be implicitly assuming that "synchronizations of memory" are totally ordered in global time. Without further specification of the memory model, there's no basis for that assumption. -- David Hopwood .