Re: [Qemu-devel] [PATCH 14/18] arch_init: skip migration_bitmap_sync for local migration

[Paolo Bonzini <pbonzini@redhat.com>]

Il 21/08/2013 09:18, Lei Li ha scritto:
> Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
> ---
>  arch_init.c |    5 +++++
>  1 files changed, 5 insertions(+), 0 deletions(-)
> 
> diff --git a/arch_init.c b/arch_init.c
> index cbbb4db..e6069eb 100644
> --- a/arch_init.c
> +++ b/arch_init.c
> @@ -375,6 +375,11 @@ static void migration_bitmap_sync(void)
>      int64_t end_time;
>      int64_t bytes_xfer_now;
>  
> +    /* No need to sync with bitmap for local migration */
> +    if (migrate_is_localhost()) {
> +        return;
> +    }
> +
>      if (!bytes_xfer_prev) {
>          bytes_xfer_prev = ram_bytes_transferred();
>      }
> 

Premature, please do this after everything is in place (including
vmsplice) and only if you find the dirty bitmap to be a significant
source of overhead.

Paolo