Commit Graph

8 Commits

Author SHA1 Message Date
Juan Quintela
0d82d0e8b9 migration: move buffered_file.c code into migration.c
This only moves the code (also from buffered_file.h to migration.h).
Fix whitespace until checkpatch is happy.

Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-12-20 23:09:36 +01:00
Juan Quintela
e4ed1541ac savevm: New save live migration method: pending
Code just now does (simplified for clarity)

    if (qemu_savevm_state_iterate(s->file) == 1) {
       vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
       qemu_savevm_state_complete(s->file);
    }

Problem here is that qemu_savevm_state_iterate() returns 1 when it
knows that remaining memory to sent takes less than max downtime.

But this means that we could end spending 2x max_downtime, one
downtime in qemu_savevm_iterate, and the other in
qemu_savevm_state_complete.

Changed code to:

    pending_size = qemu_savevm_state_pending(s->file, max_size);
    DPRINTF("pending size %lu max %lu\n", pending_size, max_size);
    if (pending_size >= max_size) {
        ret = qemu_savevm_state_iterate(s->file);
     } else {
        vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
        qemu_savevm_state_complete(s->file);
     }

So what we do is: at current network speed, we calculate the maximum
number of bytes we can sent: max_size.

Then we ask every save_live section how much they have pending.  If
they are less than max_size, we move to complete phase, otherwise we
do an iterate one.

This makes things much simpler, because now individual sections don't
have to caluclate the bandwidth (it was implossible to do right from
there).

Signed-off-by: Juan Quintela <quintela@redhat.com>

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-20 23:09:25 +01:00
Juan Quintela
188a428559 migration: remove unfreeze logic
Now that we have a thread, and blocking writes, we don't need it.

Signed-off-by: Juan Quintela <quintela@redhat.com>

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-20 23:09:25 +01:00
Juan Quintela
dd217b8732 migration: make writes blocking
Move all the writes to the migration_thread, and make writings
blocking.  Notice that are still using the iothread for everything
that we do.

Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-12-20 23:09:25 +01:00
Juan Quintela
766bd1769e migration: move migration thread init code to migrate_fd_put_ready
This way everything related with migration is run on the migration
thread and no locking is needed.

Signed-off-by: Juan Quintela <quintela@redhat.com>
2012-12-20 23:09:25 +01:00
Juan Quintela
edfa1af52f migration: make qemu_fopen_ops_buffered() return void
We want the file assignment to happen before the thread is created to
avoid locking, so we just do it before creating the thread.

Signed-off-by: Juan Quintela <quintela@redhat.com>

Reviewed-by: Orit Wasserman <owasserm@redhat.com>
2012-12-20 23:09:25 +01:00
Paolo Bonzini
1de7afc984 misc: move include files to include/qemu/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:32:39 +01:00
Paolo Bonzini
caf71f86a3 migration: move include files to include/migration/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:31:32 +01:00