View Issue Details
| ID | Project | Category | View Status | Date Submitted | Last Update |
|---|---|---|---|---|---|
| 0003915 | libmicrohttpd | thread pool | public | 2015-07-25 15:48 | 2015-09-16 14:31 |
| Reporter | Christian Grothoff | Assigned To | Christian Grothoff | ||
| Priority | normal | Severity | major | Reproducibility | have not tried |
| Status | closed | Resolution | no change required | ||
| Platform | i7 | OS | Debian GNU/Linux | OS Version | squeeze |
| Product Version | 0.9.43 | ||||
| Target Version | 0.9.43 | ||||
| Summary | 0003915: connection hangs | ||||
| Description | Markus Doppelbauer reported on the mailinglist: Maybe there is a race condition between suspending/resuming connection. This happens only if I use "poll()" - not with "epoll()". Requests were created using "wget" (http 1.0) - one after the other. What I did: The MHD-Thread calls "MHD_suspend_connection()" inside "MHD_ContentReaderCallback()". The worker thread calls "MHD_resume_connection()" if the connection is suspended. Sometimes the MHD thread sleeps forever - it does not continue to work on resume connections. The polling-variable "num_connections" is zero. The "connection_suspended"-flag and calls to "MHD_resume/suspend_connection()" are protected by a mutex. The callstack from the core-dump: #0 0x00007f38889c512d in poll () at ../sysdeps/unix/syscall-template.S:81 #1 0x00000000006786c6 in MHD_poll_all (daemon=0x359a930, may_block=1) at /home/markus/Website/gloriatv/dev/src/contrib/microhttpd/daemon.c:2485 #2 0x0000000000678ba9 in MHD_poll (daemon=0x359a930, may_block=1) at /home/markus/Website/gloriatv/dev/src/contrib/microhttpd/daemon.c:2642 #3 0x0000000000679557 in MHD_select_thread (cls=0x359a930) at /home/markus/Website/gloriatv/dev/src/contrib/microhttpd/daemon.c:2928 #4 0x00007f388a758182 in start_thread (arg=0x7f38846fb700) at pthread_create.c:312 #5 0x00007f38889d247d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111 Locals on frame #1: i = 0 timeout = -1 poll_server = 2 poll_listen = 0 tmp = 114 'r' ltimeout = 301000 poll_pipe = 1 p = 0x7f387c0008c0 num_connections = 0 pos = 0x0 next = 0x0 Thanks a lot Markus | ||||
| Steps To Reproduce | None yet. | ||||
| Tags | No tags attached. | ||||
|
|
Markus now writes: Die Sache war wohl mein Fehler - ich habe die Funktion MHD_get_daemon_info( MHD_DAEMON_INFO_CURRENT_CONNECTIONS ) von einem unbeteiligtem Thread aus augerufen. Bitte die beiden issues schließen - und danke für die Hilfe. |
| Date Modified | Username | Field | Change |
|---|---|---|---|
| 2015-07-25 15:48 | Christian Grothoff | New Issue | |
| 2015-07-25 15:51 | Christian Grothoff | Status | new => acknowledged |
| 2015-09-16 14:31 | Christian Grothoff | Note Added: 0009630 | |
| 2015-09-16 14:31 | Christian Grothoff | Assigned To | => Christian Grothoff |
| 2015-09-16 14:31 | Christian Grothoff | Status | acknowledged => resolved |
| 2015-09-16 14:31 | Christian Grothoff | Resolution | open => no change required |
| 2015-09-16 14:31 | Christian Grothoff | Product Version | => 0.9.43 |
| 2015-09-16 14:31 | Christian Grothoff | Target Version | => 0.9.43 |
| 2015-09-16 14:31 | Christian Grothoff | Status | resolved => closed |
| 2024-01-21 13:25 | Christian Grothoff | Category | libmicrohttpd multi-threaded operation => thread pool |
