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Fri, 28 Feb 2020 16:44:04 +0000 (UTC) Date: Fri, 28 Feb 2020 16:44:03 +0000 From: Stefan Hajnoczi To: Jagannathan Raman Subject: Re: [PATCH v5 47/50] multi-process: Enable support for multiple devices in remote Message-ID: <20200228164403.GA332098@stefanha-x1.localdomain> References: MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="FCuugMFkClbJLl1L" Content-Disposition: inline X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: elena.ufimtseva@oracle.com, fam@euphon.net, swapnil.ingle@nutanix.com, john.g.johnson@oracle.com, qemu-devel@nongnu.org, kraxel@redhat.com, quintela@redhat.com, mst@redhat.com, armbru@redhat.com, kanth.ghatraju@oracle.com, felipe@nutanix.com, thuth@redhat.com, ehabkost@redhat.com, konrad.wilk@oracle.com, dgilbert@redhat.com, liran.alon@oracle.com, thanos.makatos@nutanix.com, rth@twiddle.net, kwolf@redhat.com, berrange@redhat.com, mreitz@redhat.com, ross.lagerwall@citrix.com, marcandre.lureau@gmail.com, pbonzini@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" --FCuugMFkClbJLl1L Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Feb 24, 2020 at 03:55:38PM -0500, Jagannathan Raman wrote: > From: Elena Ufimtseva >=20 > Add support to allow multiple devices to be configured in the > remote process This patch allows multiple devices to be addressed over a single UNIX domain socket. This could be a scalability/performance bottleneck because an SMP guest can only talk to 1 device at a time. This approach doesn't address the qemu-storage-daemon use case where one device emulation process provides devices to multiple guests. Multiple UNIX domain sockets are needed for that. Is multiplexing multiple devices over a single connection is a desirable feature? The alternative of one UNIX domain socket per device instance seems more practical to me because it should perform better and solves the qemu-storage-daemon use case. --FCuugMFkClbJLl1L Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAl5ZQ1MACgkQnKSrs4Gr c8hfYwf/eSGyr7OXlpnFu5TR7dNACEilTRAIMr8sr03KuCcH6XTYwOyQ+1AeLFZh hNWev760tdDQ4yF69mRhF5H7VyP246yXDMp/4OA9DVeMQyuDZIf1CrH32JUhGLdO ky2UjhPBgzMQXEDLpWDBinKLFozS31UnoLl/NzOZb12BMLgDB0eEe/Ma1hS5fmpI j6Hkfg8Bwyv9QvIM40UmUW82QacDhRDdfqJd0OW/kTYgFnmAHxX7iRj2xUDnlhvc P012AAQnWS8r2MuU5VPrhLt6g0KMX9obEoXfEKZr1up0l021gzbzeaS8PGsdq9Hb tVcIgvkhWFmXW/7D9gSCGwP6obX30w== =ljcf -----END PGP SIGNATURE----- --FCuugMFkClbJLl1L--