Re: [PATCH] migration: increase max-bandwidth to 128 MiB/s (1 Gib/s)

[Greg Kurz]

On Mon, 21 Sep 2020 16:49:57 +0200
Laurent Vivier <lvivier@redhat.com> wrote:

> max-bandwidth is set by default to 32 MiB/s (256 Mib/s)
> since 2008 (5bb7910af031c).
> 
> Most of the CPUs can dirty memory faster than that now,
> and this is clearly a problem with POWER where the page
> size is 64 kiB and not 4 KiB.
> 
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---

Reviewed-by: Greg Kurz <groug@kaod.org>

>  migration/migration.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/migration/migration.c b/migration/migration.c
> index 58a5452471f9..1c4174947181 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -57,7 +57,7 @@
>  #include "qemu/queue.h"
>  #include "multifd.h"
>  
> -#define MAX_THROTTLE  (32 << 20)      /* Migration transfer speed throttling 
> */
> +#define MAX_THROTTLE  (128 << 20)      /* Migration transfer speed 
> throttling */
>  
>  /* Amount of time to allocate to each "chunk" of bandwidth-throttled
>   * data. */