> From: Jerin Jacob [mailto:jerin.ja...@caviumnetworks.com] > Sent: Friday, June 30, 2017 1:52 PM > To: Van Haaren, Harry <harry.van.haa...@intel.com> > Cc: Richardson, Bruce <bruce.richard...@intel.com>; dev@dpdk.org; > tho...@monjalon.net; > Wiles, Keith <keith.wi...@intel.com> > Subject: Re: Service lcores and Application lcores > > -----Original Message----- > > Date: Fri, 30 Jun 2017 10:00:18 +0000 > > From: "Van Haaren, Harry" <harry.van.haa...@intel.com> > > To: Jerin Jacob <jerin.ja...@caviumnetworks.com>, "Richardson, Bruce" > > <bruce.richard...@intel.com> > > CC: "dev@dpdk.org" <dev@dpdk.org>, "tho...@monjalon.net" > > <tho...@monjalon.net>, "Wiles, Keith" <keith.wi...@intel.com> > > Subject: RE: Service lcores and Application lcores
<snip previous non-related items> > > I don't think providing a remote-launch API is actually beneficial. > > Remote-launching a > single service > > is equivalent to adding that lcore as a service-core, and mapping it to > > just that single > service. > > The advantage of adding it as a service core, is future-proofing for if > > more services > need to be added > > to that core in future, and statistics of the service core infrastructure. > > A convenience > API could be > > provided to perform the core_add(), service_start(), enable_on_service() and > core_start() APIs in one. > > > > Also, the remote_launch API doesn't solve the original problem - what if an > > application > lcore wishes > > to run one iteration of a service "manually". The remote_launch style API > > does not solve > this problem. > > Agree with problem statement. But, remote_launch() operates on lcores not on > not necessary on 1:1 mapped physical cores. > > By introducing "rte_service_iterate", We are creating a parallel > infrastructure to > run the service on non DPDK service lcores aka normal lcores. > Is this really required? Is there any real advantage for > application not use builtin service lcore infrastructure, rather than > iterating over > "rte_service_iterate" and run on normal lcores. If we really want to mux > a physical core to N lcore, EAL already provides that in the form of threads. > > I think, providing too many parallel options for the same use case may be > a overkill. > > Just my 2c. The use-case that the rte_service_iterate() caters for is one where the application wishes to run a service on an "ordinary app lcore", together with an application workload. For example, the eventdev-scheduler and one worker can be run on the same lcore. If the schedule() running thread *must* be a service lcore, we would not be able to also use that lcore as an application worker core. That was my motivation for adding this API, I do agree with you above; it is a second "parallel" method to run a service. I think there's enough value in enabling the use-case as per example above to add it. Do you see enough value in the use-case above to add the API?
