The max parameter of the leaky bucket throttling algorithm can be used to
allow the guest to do bursts.
The max value is a pool of I/O that the guest can use without being throttled
at all. Throttling is triggered once this pool is empty.
Signed-off-by: NBenoit Canet <benoit@irqsave.net>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>