On Thu, Jun 2, 2022 at 9:06 AM Fredrik Hallenberg <megahal...@gmail.com> wrote:
> Hi, my application tends to get a lot of short lived incoming connections. > Messages are very short sync messages that usually can be responded with > very little processing on the server side. It works fine but I feel > that the performance is a bit lacking when many connections happen at the > same time and would like advice on how to improve it. I am using qpid > proton c++ 0.37 with epoll proactor. > My current design uses a single thread for the listener but it will > immediately push incoming messages in on_message to a queue that is handled > elsewhere. I can see that clients have to wait for a long time (up to a > minute) until they get a response, but I don't believe there is an issue on > my end as I as will quickly deal with any client messages as soon as they > show up. Rather the issues seems to be that messages are not pushed into > the queue quickly enough. > I have noticed that the pn_proactor_listen is hardcoded to use a backlog of > 16 in the default container implementation, this seems low, but I am not > sure if it is correct to change it. > Any advice apppreciated. My goal is that a client should never need to wait > more than a few seconds for a response even under reasonably high load, > maybe a few hundred connections per seconds. > I would try increasing the backlog. 16 seems low to me as well. Do you know if any of your clients are re-trying the connection setup because they overran the server's backlog? -Ted
