On Tue, May 28, 2024 at 09:06:04AM +0000, Gonglei (Arei) wrote: > Hi Peter, > > > -----Original Message----- > > From: Peter Xu [mailto:[email protected]] > > Sent: Wednesday, May 22, 2024 6:15 AM > > To: Yu Zhang <[email protected]> > > Cc: Michael Galaxy <[email protected]>; Jinpu Wang > > <[email protected]>; Elmar Gerdes <[email protected]>; > > zhengchuan <[email protected]>; Gonglei (Arei) > > <[email protected]>; Daniel P. Berrangé <[email protected]>; > > Markus Armbruster <[email protected]>; Zhijian Li (Fujitsu) > > <[email protected]>; [email protected]; Yuval Shaia > > <[email protected]>; Kevin Wolf <[email protected]>; Prasanna > > Kumar Kalever <[email protected]>; Cornelia Huck > > <[email protected]>; Michael Roth <[email protected]>; Prasanna > > Kumar Kalever <[email protected]>; Paolo Bonzini > > <[email protected]>; [email protected]; [email protected]; > > Hanna Reitz <[email protected]>; Michael S. Tsirkin <[email protected]>; > > Thomas Huth <[email protected]>; Eric Blake <[email protected]>; Song > > Gao <[email protected]>; Marc-André Lureau > > <[email protected]>; Alex Bennée <[email protected]>; > > Wainer dos Santos Moschetta <[email protected]>; Beraldo Leal > > <[email protected]>; Pannengyuan <[email protected]>; > > Xiexiangyou <[email protected]>; Fabiano Rosas <[email protected]> > > Subject: Re: [PATCH-for-9.1 v2 2/3] migration: Remove RDMA protocol handling > > > > On Fri, May 17, 2024 at 03:01:59PM +0200, Yu Zhang wrote: > > > Hello Michael and Peter, > > > > Hi, > > > > > > > > Exactly, not so compelling, as I did it first only on servers widely > > > used for production in our data center. The network adapters are > > > > > > Ethernet controller: Broadcom Inc. and subsidiaries NetXtreme BCM5720 > > > 2-port Gigabit Ethernet PCIe > > > > Hmm... I definitely thinks Jinpu's Mellanox ConnectX-6 looks more > > reasonable. > > > > https://lore.kernel.org/qemu-devel/CAMGffEn-DKpMZ4tA71MJYdyemg0Zda15 > > [email protected]/ > > > > Appreciate a lot for everyone helping on the testings. > > > > > InfiniBand controller: Mellanox Technologies MT27800 Family > > > [ConnectX-5] > > > > > > which doesn't meet our purpose. I can choose RDMA or TCP for VM > > > migration. RDMA traffic is through InfiniBand and TCP through Ethernet > > > on these two hosts. One is standby while the other is active. > > > > > > Now I'll try on a server with more recent Ethernet and InfiniBand > > > network adapters. One of them has: > > > BCM57414 NetXtreme-E 10Gb/25Gb RDMA Ethernet Controller (rev 01) > > > > > > The comparison between RDMA and TCP on the same NIC could make more > > sense. > > > > It looks to me NICs are powerful now, but again as I mentioned I don't > > think it's > > a reason we need to deprecate rdma, especially if QEMU's rdma migration has > > the chance to be refactored using rsocket. > > > > Is there anyone who started looking into that direction? Would it make > > sense > > we start some PoC now? > > > > My team has finished the PoC refactoring which works well. > > Progress: > 1. Implement io/channel-rdma.c, > 2. Add unit test tests/unit/test-io-channel-rdma.c and verifying it is > successful, > 3. Remove the original code from migration/rdma.c, > 4. Rewrite the rdma_start_outgoing_migration and > rdma_start_incoming_migration logic, > 5. Remove all rdma_xxx functions from migration/ram.c. (to prevent RDMA live > migration from polluting the core logic of live migration), > 6. The soft-RoCE implemented by software is used to test the RDMA live > migration. It's successful. > > We will be submit the patchset later.
That's great news, thank you! -- Peter Xu
