> >>> A couple small steps have been taken toward eliminating the need for > >>> this > >>> hack: the addition of the "page size index" field to struct vm_page and > >>> the > >>> addition of a similarly named parameter to pmap_enter(). However, at > >>> the > >>> moment, the only tangible effect is in the automatic prefaulting by > >>> mmap(2). Instead of establishing 96 4KB page mappings, the automatic > >>> prefaulting establishes 96 page mappings whose size is determined by the > >>> size of the physical pages that it finds in the vm object. So, the > >>> prefaulting overhead remains constant, but the coverage provided by the > >>> automatic prefaulting will vary with the underlying page size. > >> Yes, I think what we might actually want is what I mentioned in person at > >> BSDCan: some sort of flag to mmap() that malloc() could use to assume > >> that any > >> reservations are fully used when they are reserved. This would avoid the > >> need > >> to wait for all pages to be dirtied before promotion provides a superpage > >> mapping and would avoid demotions while still allowing the kernel to > >> gracefully > >> fall back to regular pages if a reservation can't be made. > >> > > > > I agree. > > I notice that, with the exception of the VM_PHYSSEG_MAX change, these > patches never made it into head or ports. Are they unsuitable for low > core-count machines, or is there some other reason not to commit them? > If not, what would it take to get these into 11.0 or 11.1 ? >
I think the two big issues are: a) there's a lot more work that needs to be done b) Adrian has had a lot of other things on his plate in the meantime. Adrian is hoping to get back to it post 11.0-RELEASE. _______________________________________________ freebsd-performance@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-performance To unsubscribe, send any mail to "freebsd-performance-unsubscr...@freebsd.org"
