Please don't drop the mailing list. A couple of people have built prototypes that combine the two messages, but the performance difference was insignificant, so we did not commit it.
On Fri, Mar 13, 2015 at 10:19:21AM +0800, Vinllen Chen wrote: > Hi, Ben, i have one more question: > Once the userspace handle the upcall message and then find a facet match, > the dpif_operate function call "dpif_flow_put__" and "dpif_execute__" > function to send the "add flow" netlink message and "execute action". But > why do not combine the two netlink messages to improving performance, > because i think the netlink message will waste time. > > On Fri, Mar 13, 2015 at 9:18 AM, Vinllen Chen <cvinl...@gmail.com> wrote: > > > Thankyou very much~ > > > > On Fri, Mar 13, 2015 at 1:16 AM, Ben Pfaff <b...@nicira.com> wrote: > > > >> Please don't drop the mailing list. > >> > >> On Fri, Mar 13, 2015 at 12:04:45AM +0800, Vinllen Chen wrote: > >> > Thankyou for your reply, Ben! There are two derivative question: > >> > 1.Does the datapath also use multiple threads for receving netlink > >> message ? > >> > >> The kernel always processes Netlink messages in the same thread that > >> sent it. > >> > >> > 2.So I can understand the receive process: Once receive a netlink > >> message, > >> > the main thread will create a new thread to handle it???that means one > >> thread > >> > for one connection? > >> > >> No, that would be much too expensive. Userspace maintains a fixed > >> thread pool. > >> > >> > On Thu, Mar 12, 2015 at 11:38 PM, Ben Pfaff <b...@nicira.com> wrote: > >> > > >> > > On Wed, Mar 11, 2015 at 07:14:05PM +0800, Vinllen Chen wrote: > >> > > > When i read the source code of ovs, i found the userspace > >> receives > >> > > > netlink message by epoll. But in the explanition of dpif.h, datapath > >> > > starts > >> > > > many threads to receiving netlink. > >> > > > Could anybody give me a definite answer that how does the > >> userspace > >> > > and > >> > > > kernel space receive netlink messages. > >> > > > >> > > epoll doesn't receive anything; it doesn't have any functionality for > >> > > receiving anything. > >> > > > >> > > Userspace uses netlink sockets to receive netlink messages from the > >> > > kernel. It does use multiple threads for that. > >> > > > >> > > > > _______________________________________________ discuss mailing list discuss@openvswitch.org http://openvswitch.org/mailman/listinfo/discuss
