> -----Original Message-----
> From: Michael S. Tsirkin [mailto:m...@redhat.com]
> Sent: Wednesday, June 5, 2024 3:57 PM
> To: Gonglei (Arei) <arei.gong...@huawei.com>
> Cc: qemu-devel@nongnu.org; pet...@redhat.com; yu.zh...@ionos.com;
> mgal...@akamai.com; elmar.ger...@ionos.com; zhengchuan
> <zhengch...@huawei.com>; berra...@redhat.com; arm...@redhat.com;
> lizhij...@fujitsu.com; pbonz...@redhat.com; Xiexiangyou
> <xiexiang...@huawei.com>; linux-r...@vger.kernel.org; lixiao (H)
> <lixia...@huawei.com>; jinpu.w...@ionos.com; Wangjialin
> <wangjiali...@huawei.com>
> Subject: Re: [PATCH 0/6] refactor RDMA live migration based on rsocket API
>
> On Tue, Jun 04, 2024 at 08:14:06PM +0800, Gonglei wrote:
> > From: Jialin Wang <wangjiali...@huawei.com>
> >
> > Hi,
> >
> > This patch series attempts to refactor RDMA live migration by
> > introducing a new QIOChannelRDMA class based on the rsocket API.
> >
> > The /usr/include/rdma/rsocket.h provides a higher level rsocket API
> > that is a 1-1 match of the normal kernel 'sockets' API, which hides
> > the detail of rdma protocol into rsocket and allows us to add support
> > for some modern features like multifd more easily.
> >
> > Here is the previous discussion on refactoring RDMA live migration
> > using the rsocket API:
> >
> > https://lore.kernel.org/qemu-devel/20240328130255.52257-1-philmd@linar
> > o.org/
> >
> > We have encountered some bugs when using rsocket and plan to submit
> > them to the rdma-core community.
> >
> > In addition, the use of rsocket makes our programming more convenient,
> > but it must be noted that this method introduces multiple memory
> > copies, which can be imagined that there will be a certain performance
> > degradation, hoping that friends with RDMA network cards can help verify,
> thank you!
>
> So you didn't test it with an RDMA card?
Yep, we tested it by Soft-ROCE.
> You really should test with an RDMA card though, for correctness as much as
> performance.
>
We will, we just don't have RDMA cards environment on hand at the moment.
Regards,
-Gonglei
>
> > Jialin Wang (6):
> > migration: remove RDMA live migration temporarily
> > io: add QIOChannelRDMA class
> > io/channel-rdma: support working in coroutine
> > tests/unit: add test-io-channel-rdma.c
> > migration: introduce new RDMA live migration
> > migration/rdma: support multifd for RDMA migration
> >
> > docs/rdma.txt | 420 ---
> > include/io/channel-rdma.h | 165 ++
> > io/channel-rdma.c | 798 ++++++
> > io/meson.build | 1 +
> > io/trace-events | 14 +
> > meson.build | 6 -
> > migration/meson.build | 3 +-
> > migration/migration-stats.c | 5 +-
> > migration/migration-stats.h | 4 -
> > migration/migration.c | 13 +-
> > migration/migration.h | 9 -
> > migration/multifd.c | 10 +
> > migration/options.c | 16 -
> > migration/options.h | 2 -
> > migration/qemu-file.c | 1 -
> > migration/ram.c | 90 +-
> > migration/rdma.c | 4205 +----------------------------
> > migration/rdma.h | 67 +-
> > migration/savevm.c | 2 +-
> > migration/trace-events | 68 +-
> > qapi/migration.json | 13 +-
> > scripts/analyze-migration.py | 3 -
> > tests/unit/meson.build | 1 +
> > tests/unit/test-io-channel-rdma.c | 276 ++
> > 24 files changed, 1360 insertions(+), 4832 deletions(-) delete mode
> > 100644 docs/rdma.txt create mode 100644 include/io/channel-rdma.h
> > create mode 100644 io/channel-rdma.c create mode 100644
> > tests/unit/test-io-channel-rdma.c
> >
> > --
> > 2.43.0
