Re: [Qemu-devel] [RFC v6 18/27] monitor: send event when command queue full

[Peter Xu]

On Thu, Dec 21, 2017 at 07:42:46PM +0800, Fam Zheng wrote:
> On Tue, 12/19 16:45, Peter Xu wrote:
> > Set maximum QMP command queue length to 8.  If queue full, instead of
> > queue the command, we directly return a "command-dropped" event, telling
> > client that specific command is dropped.
> > 
> > Note that this flow control mechanism is only valid if OOB is enabled.
> > If it's not, the effective queue length will always be 1, which strictly
> > follows original behavior of QMP command handling (which never drop
> > messages).
> > 
> > Signed-off-by: Peter Xu <address@hidden>
> > ---
> >  monitor.c | 17 ++++++++++++++++-
> >  1 file changed, 16 insertions(+), 1 deletion(-)
> > 
> > diff --git a/monitor.c b/monitor.c
> > index ed9a741d06..b571866659 100644
> > --- a/monitor.c
> > +++ b/monitor.c
> > @@ -4038,6 +4038,8 @@ static void monitor_qmp_bh_dispatcher(void *data)
> >      }
> >  }
> >  
> > +#define  QMP_REQ_QUEUE_LEN_MAX  (8)
> 
> Is this limit introspectable on QMP?

Not yet.  IMHO it's really QMP internal stuff, and I see no benefit so
far for a client to know about this...

-- 
Peter Xu