Messages in this thread | | | Date | Tue, 19 Jan 2010 10:44:23 +0200 | Subject | Re: [PATCH v6] add MAP_UNLOCKED mmap flag | From | Pekka Enberg <> |
| |
Hi Gleb,
On Tue, Jan 19, 2010 at 10:26 AM, Gleb Natapov <gleb@redhat.com> wrote: >> design would still be broken, no? Did you try using (or extending) >> posix_madvise(MADV_DONTNEED) for the guest address space? It seems to > After mlockall() I can't even allocate guest address space. Or do you mean > instead of mlockall()? Then how MADV_DONTNEED will help? It just drops > page table for the address range (which is not what I need) and does not > have any long time effect.
Oh right, MADV_DONTNEED is no good.
On Tue, Jan 19, 2010 at 10:26 AM, Gleb Natapov <gleb@redhat.com> wrote: >> me that you're trying to use a big hammer (mlock) when a polite hint >> for the VM would probably be sufficient for it do its job. >> > I what to tell to VM "swap this, don't swap that" and as far as I see > there is no other way to do it currently.
Yeah, which is why I was suggesting that maybe posix_madvise() needs to be extended to have a MADV_NEED_BUT_LESS_IMPORTANT flag that can be used as a hint by mm/vmscan.c to first swap the guest address spaces.
Pekka
| |