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

Minchan Kim
2013-10-08T03:06:20Z

Hi KOSAKI,

On Mon, Oct 07, 2013 at 10:51:18PM -0400, KOSAKI Motohiro wrote:
> >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?

https://lkml.org/lkml/2013/3/12/105

--
Kind regards,
Minchan Kim