Re: [Qemu-devel] Where is the VM live migration code?

[Jidong Xiao]

On Mon, Nov 17, 2014 at 5:29 PM, Zhang Haoyu <address@hidden> wrote:
>> Hi,
>>
>> I saw this page:
>>
>> http://www.linux-kvm.org/page/Migration.
>>
>> It looks like Migration is a feature provided by KVM? But when I look
>> at the Linux kernel source code, i.e., virt/kvm, and arch/x86/kvm, I
>> don't see the code for this migration feature.
>>
> Most of live migration code is in qemu migration.c, savevm.c, arch_init.c,
> block-migration.c, and the other devices's save/load handler, .etc,
> only log/sync dirty page implemented in kernel.
> You can read the most important function migration_thread(),
> process_incoming_migration_co().
>
Great, thanks Haoyu! I will try to understand these parts of code first.

-Jidong

>> So I wonder where is the source code for the live migration? Is it
>>purely implemented in user space? Because I see there are the
>> following files in the qemu source code:
>>
>> migration.c  migration-exec.c  migration-fd.c  migration-rdma.c
>> migration-tcp.c  migration-unix.c
>>
>> If I wish to understand the implementation of migration in Qemu/KVM,
>> are these above files the ones I should read? Thanks.
>>
>> -Jidong
>