On Fri, 26 Aug 2005, Ray Fucillo wrote: > However, there is still a need that the child, once successfully forked, is > operational reasonably quickly. I suspect that Ross's idea of paging in > everything after the first fault would not be optimal for us, because we'd > still be talking about hundreds of ms of work done before the child does > anything useful.
Simply skipping the page table setup of MAP_SHARED regions should be enough to fix this issue. > It would still be far better than the behavior we have today because > that time would no longer be synchronous with the fork(). Filling in all the page table entries at the first fault to a VMA doesn't make much sense, IMHO. The reason I think this is that people have experimented with prefaulting already resident pages at page fault time, and those experiments have never shown a conclusive benefit. Now, if doing such prefaulting for normal processes does not show a benefit - why would it be beneficial to recently forked processes with a huge SHM area ? I suspect we would be better off without that extra complexity, unless there is a demonstrated benefit to it. -- All Rights Reversed - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
