From: Eric Blake <eblake@redhat.com>
To: Gary Jordan <jordgary@gmail.com>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] Qemu only uses a Qemu File to communicate in two hosts?
Date: Mon, 30 Jun 2014 15:08:50 -0600 [thread overview]
Message-ID: <53B1D1E2.5030105@redhat.com> (raw)
In-Reply-To: <CAF8TkMKKguN4uXOFOw9va7mnB_QthTrVATJHz3E9ESEXRUOOFg@mail.gmail.com>
[-- Attachment #1: Type: text/plain, Size: 969 bytes --]
On 06/30/2014 03:02 PM, Gary Jordan wrote:
> Hi,
> Does Qemu only use the QEMUFile to load the state of VM after migration?
Normally, yes. Migration must work as a one-way protocol in the common
case when used with default options.
There is a migration mode that uses RDMA which requires bi-directional
communication in order to speed up aspects of memory migration. But
this mode is transparent to the guest, and requires you to take extra
steps at both source and destination (along with having an infiniband
connection capable of RDMA communication between the two hosts).
> Is there a way for two vm guests to communicate like two threads or
> processes?
If there is, it has nothing to do with migration. It sounds like you
are asking about ivshmem and/or virtio; if so, search the archives for
recent discussions on the topic.
--
Eric Blake eblake redhat com +1-919-301-3266
Libvirt virtualization library http://libvirt.org
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 604 bytes --]
next prev parent reply other threads:[~2014-06-30 21:09 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-06-30 21:02 [Qemu-devel] Qemu only uses a Qemu File to communicate in two hosts? Gary Jordan
2014-06-30 21:08 ` Eric Blake [this message]
2014-06-30 21:58 ` Gary Jordan
2014-06-30 22:30 ` Eric Blake
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=53B1D1E2.5030105@redhat.com \
--to=eblake@redhat.com \
--cc=jordgary@gmail.com \
--cc=qemu-devel@nongnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).