Marcelo Tosatti wrote: > On Sat, Jan 19, 2008 at 04:37:43PM -0600, Anthony Liguori wrote: > >> Avi Kivity wrote: >> >>> Rusty Russell wrote: >>> >>>> After discussions with Anthony Liguori, it seems that the virtio >>>> balloon can be made even simpler. Here's my attempt. >>>> >>>> Since the balloon requires Guest cooperation anyway, there seems >>>> little reason to force it to tell the Host when it wants to reuse a >>>> page. It can simply fault it in. >>>> >>>> >>>> >>> Faulting is synchronous, while deflating is (or can be made) >>> asynchronous. If the host needs to do some work to get the memory, the >>> guest will be slowed down considerably. >>> >> Good point. Basically, we have two page hinting operations which >> roughly correspond to madvise(MADV_DONTNEED) and madvise(MADV_WILLNEED). >> > > Also, the simplified driver does not handle errors at all. > > I don't think that assuming madvise() can't fail is a good thing. >
I don't think the host should be communicating to the guest if madvise() fails. The notification is a hint to the host. The guest doesn't know what the host is doing in response to that hint. Regards, Anthony Liguori ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
