On 09/09/2016 05:00 PM, Josef Bacik wrote: >> Right. Alternatively, you could perhaps make it so that the lost >> connection is removed, unack'd requests on that connection are resent, >> and the session moves on with one less connection (unless the lost >> connection is the last one, in which case we die as before). That might >> be too much work and not worth it though. > > Yeah I wasn't sure if we could just randomly remove hw queue's in blk mq > while the device is still up. If that is in fact easy to do then I'm in > favor of trucking along with less connections than we originally had, > otherwise I think it'll be too big of a pain. Also some users (Facebook > in this case) would rather the whole thing fail so we can figure out > what went wrong rather than suddenly going at a degraded performance.
We can do that online. We do that for CPU hotplug/unplug events, and we also expose that functionality to drivers through blk_mq_update_nr_hw_queues(). So yes, should be trivial to support from nbd. -- Jens Axboe ------------------------------------------------------------------------------ _______________________________________________ Nbd-general mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/nbd-general
