[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v3 20/29] postcopy: postcopy_notify_shared_wake
From: |
Peter Xu |
Subject: |
Re: [Qemu-devel] [PATCH v3 20/29] postcopy: postcopy_notify_shared_wake |
Date: |
Wed, 7 Mar 2018 18:13:25 +0800 |
User-agent: |
Mutt/1.9.1 (2017-09-22) |
On Tue, Mar 06, 2018 at 10:54:18AM +0000, Dr. David Alan Gilbert wrote:
[...]
> > Basically above was what I thought - to record the faulted addresses
> > with specific PostcopyFD when page fault happened, then we may know
> > which page(s) will a PostcopyFD need. But when with that, we'll
> > possibly need a lock to protect the information (or any other sync
> > method).
>
> OK, but I think you're suggesting building a whole new data structure to
> know which ones need notifying; that sounds like a lot of extra
> complexity for not much gain.
Yes we may need a new structure (or just a list of addresses?), and
indeed I have no idea on how that would help us. I think it depends
on how many useless wakeup we will have, and how expensive is each of
such a wakeup notification. Again, I think current solution is good
enough as long as we don't see explicit blocker on performance side,
and we can rethink that when really needed. Thanks,
--
Peter Xu