Am 08.06.2017 um 20:21 hat Manos Pitsidianakis geschrieben:
to maintain compatibility with the existing interfaces. We will have to
automatically insert or remove new nodes if 'block_set_io_throttle' is
used, but let's not extend it. It only makes things complicated.
If people are using new features, they will be using new interfaces and
we can make them use more natural syntax. For example, we can expect
that they create throttle nodes manually (management tools always, human
users at least for more complicated cases). What we may want is to
update the settings of a throttle node at runtime (though inserting a
new filter and then removing the old one could do the trick as well).
If we want to change the settings of a throttle node, then I think the
appropriate low-level interface is bdrv_reopen(). We need to figure out
whether we can expose a full bdrv_reopen() on QMP or whether we need
more specific commands. I'd prefer finally doing the "real thing" rather
than adding more and more special-case commands to update nodes.