Re: [PATCH 05/14] vrange: Add new vrange(2) system call

KOSAKI Motohiro
2013-10-08T02:51:22Z

> Maybe, int madvise5(addr, length, MADV_DONTNEED|MADV_LAZY|MADV_SIGBUS,
> &purged, &ret);
>
> Another reason to make it hard is that madvise(2) is tight coupled with
> with vmas split/merge. It needs mmap_sem's write-side lock and it hurt
> anon-vrange test performance much heavily and userland might want to
> make volatile range with small unit like "page size" so it's undesireable
> to make it with vma. Then, we should filter out to avoid vma split/merge
> in implementation if only MADV_LAZY case? Doable but it could make code
> complicated and lost consistency with other variant of madvise.

I haven't seen your performance test result. Could please point out URLs?