From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

Hi,
  This set adds support for multipath TCP (mptcp), and has
been tested for migration and (lightly) for NBD.

  Multipath-tcp is a bit like bonding, but at L3; you can use
it to handle failure, but can also use it to split traffic across
multiple interfaces.

  Using a pair of 10Gb interfaces, I've managed to get 19Gbps
(with the only tuning being using huge pages and turning the MTU up).

  It needs a bleeding-edge Linux kernel (in some older ones you get
false accept messages for the subflows), and a C lib that has the
constants defined (as current glibc does).

  To use it you just need to append ,mptcp to an address; for migration:

  -incoming tcp:0:4444,mptcp
  migrate -d tcp:192.168.11.20:4444,mptcp

For nbd:

  (qemu) nbd_server_start 0.0.0.0:3333,mptcp=on

  -blockdev driver=nbd,server.type=inet,server.host=192.168.11.20,server.port=3333,server.mptcp=on,node-name=nbddisk,export=mydisk \
  -device virtio-blk,drive=nbddisk,id=disk0

(Many of the other NBD address parsers/forms would need extra work)

  All comments welcome.

Dave

v2
  Use of if defined(...) in the json file based on feedback
  A few missing ifdef's (from a bsd build test)
  Added nbd example.


Dr. David Alan Gilbert (5):
  channel-socket: Only set CLOEXEC if we have space for fds
  io/net-listener: Call the notifier during finalize
  migration: Add cleanup hook for inwards migration
  migration/socket: Close the listener at the end
  sockets: Support multipath TCP

 io/channel-socket.c   |  8 ++++----
 io/dns-resolver.c     |  4 ++++
 io/net-listener.c     |  3 +++
 migration/migration.c |  3 +++
 migration/migration.h |  4 ++++
 migration/multifd.c   |  5 +++++
 migration/socket.c    | 24 ++++++++++++++++++------
 qapi/sockets.json     |  5 ++++-
 util/qemu-sockets.c   | 23 +++++++++++++++++++++++
 9 files changed, 68 insertions(+), 11 deletions(-)

-- 
2.31.1

* Dr. David Alan Gilbert (git) (dgilbert@redhat.com) wrote:
> From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> 
> Hi,
>   This set adds support for multipath TCP (mptcp), and has
> been tested for migration and (lightly) for NBD.
> 
>   Multipath-tcp is a bit like bonding, but at L3; you can use
> it to handle failure, but can also use it to split traffic across
> multiple interfaces.
> 
>   Using a pair of 10Gb interfaces, I've managed to get 19Gbps
> (with the only tuning being using huge pages and turning the MTU up).
> 
>   It needs a bleeding-edge Linux kernel (in some older ones you get
> false accept messages for the subflows), and a C lib that has the
> constants defined (as current glibc does).
> 
>   To use it you just need to append ,mptcp to an address; for migration:
> 
>   -incoming tcp:0:4444,mptcp
>   migrate -d tcp:192.168.11.20:4444,mptcp
> 
> For nbd:
> 
>   (qemu) nbd_server_start 0.0.0.0:3333,mptcp=on
> 
>   -blockdev driver=nbd,server.type=inet,server.host=192.168.11.20,server.port=3333,server.mptcp=on,node-name=nbddisk,export=mydisk \
>   -device virtio-blk,drive=nbddisk,id=disk0
> 
> (Many of the other NBD address parsers/forms would need extra work)
> 
>   All comments welcome.
> 
> Dave

Queued

> 
> v2
>   Use of if defined(...) in the json file based on feedback
>   A few missing ifdef's (from a bsd build test)
>   Added nbd example.
> 
> 
> Dr. David Alan Gilbert (5):
>   channel-socket: Only set CLOEXEC if we have space for fds
>   io/net-listener: Call the notifier during finalize
>   migration: Add cleanup hook for inwards migration
>   migration/socket: Close the listener at the end
>   sockets: Support multipath TCP
> 
>  io/channel-socket.c   |  8 ++++----
>  io/dns-resolver.c     |  4 ++++
>  io/net-listener.c     |  3 +++
>  migration/migration.c |  3 +++
>  migration/migration.h |  4 ++++
>  migration/multifd.c   |  5 +++++
>  migration/socket.c    | 24 ++++++++++++++++++------
>  qapi/sockets.json     |  5 ++++-
>  util/qemu-sockets.c   | 23 +++++++++++++++++++++++
>  9 files changed, 68 insertions(+), 11 deletions(-)
> 
> -- 
> 2.31.1
> 
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK