Excerpts from Joe Gordon's message of 2015-05-07 17:43:06 -0700: > On May 7, 2015 2:37 AM, "Sahid Orentino Ferdjaoui" < > sahid.ferdja...@redhat.com> wrote: > > > > Hi, > > > > The primary point of this expected discussion around asynchronous > > communication is to optimize performance by reducing latency. > > > > For instance the design used in Nova and probably other projects let > > able to operate ascynchronous operations from two way. > > > > 1. When communicate between inter-services > > 2. When communicate to the database > > > > 1 and 2 are close since they use the same API but I prefer to keep a > > difference here since the high level layer is not the same. > > > > From Oslo Messaging point of view we currently have two methods to > > invoke an RPC: > > > > Cast and Call: The first one is not bloking and will invoke a RPC > > without to wait any response while the second will block the > > process and wait for the response. > > > > The aim is to add new method which will return without to block the > > process an object let's call it "Future" which will provide some basic > > methods to wait and get a response at any time. > > > > The benefice from Nova will comes on a higher level: > > > > 1. When communicate between services it will be not necessary to block > > the process and use this free time to execute some other > > computations. > > Isn't this what the use of green threads (and eventlet) is supposed to > solve. Assuming my understanding is correct, and we can fix any issues > without adding async oslo.messaging, then adding yet another async pattern > seems like a bad thing.
Yes, this is what the various executors in the messaging library do, including the eventlet-based executor we use by default. Where are you seeing nova block on RPC calls? Doug __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
