On Thu, 23 Sep 2021 19:57:23 +0300 Evgeny Grin <k...@yandex.ru> wrote:
> On 23.09.2021 18:43, José Bollo wrote: > >> For sure you can run MHD with "external poll" mode, but you must > >> ensure that only single thread is calling MHD_run() at any given > >> moment of time. > > > > Okay, that is a good hint, thanks. I'm going to first track > > concurrent use of MHD_run. FYI, I tried the latest git and got the > > same issue. > >> If you want to call several copies of MHD_run(), make sure that you > >> have individual copies of MHD for each thread (start MHD by > >> MHD_start_daemon() for every thread). > > > > I don't want that, because it implies differents port I suppose. > > Even if MHD is doing internal accept(), you still can use > MHD_OPTION_LISTENING_ADDRESS_REUSE parameter to bind to the same > port. Or provide your own socket. > However as I can see below, it's not applicable for your case as you > are not using MHD to listen for new connections. > > > >> Alternatively, you can use MHD with its own threading mode. MHD can > >> run treads per connection or use thread pool. > >> > >> Can you give more details how you use MHD? Which flags are used? > > > > flags = MHD_USE_EPOLL > > | MHD_ALLOW_UPGRADE > > | MHD_USE_TCP_FASTOPEN > > | MHD_USE_NO_LISTEN_SOCKET > > | MHD_ALLOW_SUSPEND_RESUME; > > Do you use suspend/resume of connections? yes for websocket upgrade but it is not relevant in the case. > > > >> Why do you use external threads instead of MHD internal treads? > > > > The program has a job scheduler that manages threads on its own. It > > also serves other protocols that HTTP(S). > > It is still hard to see where is the problem. Actually responses are > thread-safe and shouldn't create any such kind of problems. > > Could you share you access handler callback code? > Where do you generate responses? > Where do you queue responses? I think that the clue about re-entering MHD_run is the good one. I'm going to follow that path tomorrow and will let you know. The code is public but you know, it is a pain to read someone else code and this part is poorly commented. Best regards José
