From: Paolo Bonzini <pbonzini@redhat.com>
To: "Michael R. Hines" <mrhines@linux.vnet.ibm.com>
Cc: aliguori@us.ibm.com, quintela@redhat.com, qemu-devel@nongnu.org,
owasserm@redhat.com, abali@us.ibm.com, mrhines@us.ibm.com,
gokul@us.ibm.com, chegu_vinod@hp.com, knoel@redhat.com
Subject: Re: [Qemu-devel] [PATCH v11 14/15] rdma: introduce MIG_STATE_NONE and change MIG_STATE_SETUP state transition
Date: Tue, 25 Jun 2013 23:06:08 +0200 [thread overview]
Message-ID: <51CA0640.1040507@redhat.com> (raw)
In-Reply-To: <51CA03FF.1000806@linux.vnet.ibm.com>
Il 25/06/2013 22:56, Michael R. Hines ha scritto:
>>
> I was wrong - this does require a protocol extension.
>
> This is because the RDMA transfers are asynchronous, and thus
> we cannot know in advance that it is safe to unregister the memory
> associated with each individual transfer before the transfer actually
> completes.
>
> While the destination currently uses the protocol to participate in
> *registering* the page, the destination does not participate in the
> RDMA transfers themselves, only the source does, and thus would
> require a new exchange of messages to block and instruct the
> destination to unpin the memory.
Yes, that's what I recalled too (really what mst told me :)). Does it
need to be blocking though? As long as the pinning is blocking, and
messages are processed in order, the source can proceed immediately
after sending an unpin message. This assumes of course that the chunk
is not being transmitted, and I am not sure how easy the source can
determine that.
Paolo
next prev parent reply other threads:[~2013-06-25 21:06 UTC|newest]
Thread overview: 56+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-06-25 1:57 [Qemu-devel] [PATCH v11 00/15] rdma: migration support mrhines
2013-06-25 1:57 ` [Qemu-devel] [PATCH v11 01/15] rdma: add documentation mrhines
2013-06-25 11:54 ` Juan Quintela
2013-06-25 1:57 ` [Qemu-devel] [PATCH v11 02/15] rdma: introduce qemu_update_position() mrhines
2013-06-25 9:24 ` Juan Quintela
2013-06-25 1:57 ` [Qemu-devel] [PATCH v11 03/15] rdma: export yield_until_fd_readable() mrhines
2013-06-25 9:26 ` Juan Quintela
2013-06-25 1:57 ` [Qemu-devel] [PATCH v11 04/15] rdma: export throughput w/ MigrationStats QMP mrhines
2013-06-25 9:27 ` Juan Quintela
2013-06-25 13:36 ` Michael R. Hines
2013-06-25 1:57 ` [Qemu-devel] [PATCH v11 05/15] rdma: introduce qemu_file_mode_is_not_valid() mrhines
2013-06-25 9:28 ` Juan Quintela
2013-06-25 1:57 ` [Qemu-devel] [PATCH v11 06/15] rdma: export qemu_fflush() mrhines
2013-06-25 9:29 ` Juan Quintela
2013-06-25 1:57 ` [Qemu-devel] [PATCH v11 07/15] rdma: introduce ram_handle_compressed() mrhines
2013-06-25 9:30 ` Juan Quintela
2013-06-25 1:57 ` [Qemu-devel] [PATCH v11 08/15] rdma: introduce qemu_ram_foreach_block() mrhines
2013-06-25 9:30 ` Juan Quintela
2013-06-25 1:57 ` [Qemu-devel] [PATCH v11 09/15] rdma: new QEMUFileOps hooks mrhines
2013-06-25 11:51 ` Juan Quintela
2013-06-25 13:38 ` Michael R. Hines
2013-06-25 13:50 ` Paolo Bonzini
2013-06-25 1:58 ` [Qemu-devel] [PATCH v11 10/15] rdma: introduce capability x-rdma-pin-all mrhines
2013-06-25 9:33 ` Juan Quintela
2013-06-25 1:58 ` [Qemu-devel] [PATCH v11 11/15] rdma: core logic mrhines
2013-06-25 12:05 ` Juan Quintela
2013-06-25 13:39 ` Michael R. Hines
2013-06-25 16:31 ` Vasilis Liaskovitis
2013-06-25 16:41 ` Paolo Bonzini
2013-06-25 18:38 ` Michael R. Hines
2013-06-25 1:58 ` [Qemu-devel] [PATCH v11 12/15] rdma: send pc.ram mrhines
2013-06-25 1:58 ` [Qemu-devel] [PATCH v11 13/15] rdma: allow state transitions between other states besides ACTIVE mrhines
2013-06-25 9:40 ` Juan Quintela
2013-06-25 1:58 ` [Qemu-devel] [PATCH v11 14/15] rdma: introduce MIG_STATE_NONE and change MIG_STATE_SETUP state transition mrhines
2013-06-25 9:49 ` Juan Quintela
2013-06-25 10:13 ` Paolo Bonzini
2013-06-25 13:44 ` Michael R. Hines
2013-06-25 13:53 ` Paolo Bonzini
2013-06-25 14:54 ` Michael R. Hines
2013-06-25 14:55 ` Paolo Bonzini
2013-06-25 16:57 ` Michael R. Hines
2013-06-25 20:56 ` Michael R. Hines
2013-06-25 21:06 ` Paolo Bonzini [this message]
2013-06-26 0:31 ` Michael R. Hines
2013-06-26 6:37 ` Paolo Bonzini
2013-06-26 12:37 ` Michael R. Hines
2013-06-26 12:39 ` Paolo Bonzini
2013-06-26 14:09 ` Michael R. Hines
2013-06-26 14:57 ` Paolo Bonzini
2013-06-26 19:25 ` Michael R. Hines
2013-06-25 14:17 ` Juan Quintela
2013-06-25 17:02 ` Michael R. Hines
2013-06-25 18:48 ` Michael R. Hines
2013-06-25 13:40 ` Michael R. Hines
2013-06-25 1:58 ` [Qemu-devel] [PATCH v11 15/15] rdma: account for the time spent in MIG_STATE_SETUP through QMP mrhines
2013-06-25 9:50 ` Juan Quintela
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