On 08/06/2014 07:54 PM, Jay Pipes wrote: > I bring this up on the mailing list because I think Liyi's patch offers > an interesting future direction to the way that we think about our retry > approach in Nova. Instead of having hard-coded or configurable interval > times, I think Liyi's approach of calculating the interval length based > on some input values is a good direction to take. >
This indeed is a problem that we've seen bite us a number of times, and I tried to solve it by proposing [1] but didn't get to work on it further yet. Having said that - after thinking about it more, I was not sure I like my own approach in [1] on the grounds of it being too generic (and overly elaborate) for the particular problem it is solving. I was then thinking of something similar to what is proposed here, where we would have a waiting time that is a function of a value that we could query Cinder on. Allocation rate proposed here seems to fit this nicely, but in my mind we would have a way to query cinder about it instead of hardcoding it, however this can be done later and in cooperation with the Cinder team. > > 2) We should deprecate the CONF.block_device_allocate_retries_interval > option only, and keep the CONF.block_device_allocate_retries > configuration option as-is, changing the help text to read something > like "Max number of retries. We calculate the interval of the retry > based on the size of the volume." > I'd go with this as the number of retries can still be useful as a tool for easy workaround and troubleshooting, but I'd put a big disclaimer that it is mostly meant for debugging/workaround purposes. N. [1] https://review.openstack.org/#/c/87546/ _______________________________________________ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
