On Tue, Sep 29, 2009 at 10:39:57AM -0500, Anthony Liguori wrote: > Dietmar Maurer wrote: >> this patch solves the problem by calculation an average bandwidth. >> > > Can you take a look Glauber? > > Regards, > > Anthony Liguori > >> - Dietmar >> >> >>> -----Original Message----- >>> From: [email protected] [mailto:[email protected]] On >>> Behalf Of Dietmar Maurer >>> Sent: Dienstag, 29. September 2009 16:37 >>> To: kvm >>> Subject: RE: migrate_set_downtime bug >>> >>> Seems the bwidth calculation is the problem. The code simply does: >>> >>> bwidth = (bytes_transferred - bytes_transferred_last) / timediff >>> >>> but I assume network traffic is buffered, so calculated bwidth is >>> sometimes much too high. On the other hand, you are just calculating the total since the beginning of migration, which is not right either.
Also, if this is really the case (buffered), then the bandwidth capping part of migration is also wrong. Have you compared the reported bandwidth to your actual bandwith ? I suspect the source of the problem can be that we're currently ignoring the time we take to transfer the state of the devices, and maybe it is not negligible. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
