On Thu, May 11, 2023 at 12:36 PM Brian Hutchinson <b.hutch...@gmail.com> wrote: > > ... more background. I've always used ltt in the kernel so I don't > have much experience with the user side of it and especially > multi-threaded, multi-core so I'm probably missing some fundamental > concepts that I need to understand. > > Regards, > > Brian
I'm currently reading up on the new v2.13 "Recording event rule and event record" features. I came to 2.13 because I want to be able to trigger snapshots on an event so I don't fill up storage on an embedded device. After I start lttng-systemd --daemonize and then start my app, I see this when I do lttng list --userspace: # lttng-sessiond --daemonize [ 85.180717] LTTng: Loaded modules v2.13.9 (Nordicit�é) [ 85.186103] LTTng: Experimental bitwise enum enabled. # lttng list --userspace UST events: ------------- PID: 617 - Name: sh lttng_ust_libc:posix_memalign (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:memalign (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:realloc (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:calloc (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:free (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:malloc (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_pthread:pthread_mutex_unlock (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_pthread:pthread_mutex_trylock (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_pthread:pthread_mutex_lock_acq (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_pthread:pthread_mutex_lock_req (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:dlclose (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:debug_link (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:build_id (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:dlmopen (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:dlopen (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG (loglevel: TRACE_DEBUG (14)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_LINE (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_FUNCTION (loglevel: TRACE_DEBUG_FUNCTION (12)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_UNIT (loglevel: TRACE_DEBUG_UNIT (11)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_MODULE (loglevel: TRACE_DEBUG_MODULE (10)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_PROCESS (loglevel: TRACE_DEBUG_PROCESS (9)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_PROGRAM (loglevel: TRACE_DEBUG_PROGRAM (8)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_SYSTEM (loglevel: TRACE_DEBUG_SYSTEM (7)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_INFO (loglevel: TRACE_INFO (6)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_NOTICE (loglevel: TRACE_NOTICE (5)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_WARNING (loglevel: TRACE_WARNING (4)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_ERR (loglevel: TRACE_ERR (3)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_CRIT (loglevel: TRACE_CRIT (2)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_ALERT (loglevel: TRACE_ALERT (1)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_EMERG (loglevel: TRACE_EMERG (0)) (type: tracepoint) lttng_ust_tracef:event (loglevel: TRACE_DEBUG (14)) (type: tracepoint) lttng_ust_lib:unload (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_lib:debug_link (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_lib:build_id (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_lib:load (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:end (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:procname (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:debug_link (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:build_id (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:bin_info (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:start (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) PID: 601 - Name: /usr/loal/bin/my_app lttng_ust_libc:posix_memalign (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:memalign (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:realloc (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:calloc (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:free (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:malloc (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_pthread:pthread_mutex_unlock (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_pthread:pthread_mutex_trylock (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_pthread:pthread_mutex_lock_acq (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_pthread:pthread_mutex_lock_req (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:dlclose (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:debug_link (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:build_id (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:dlmopen (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:dlopen (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG (loglevel: TRACE_DEBUG (14)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_LINE (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_FUNCTION (loglevel: TRACE_DEBUG_FUNCTION (12)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_UNIT (loglevel: TRACE_DEBUG_UNIT (11)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_MODULE (loglevel: TRACE_DEBUG_MODULE (10)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_PROCESS (loglevel: TRACE_DEBUG_PROCESS (9)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_PROGRAM (loglevel: TRACE_DEBUG_PROGRAM (8)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_SYSTEM (loglevel: TRACE_DEBUG_SYSTEM (7)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_INFO (loglevel: TRACE_INFO (6)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_NOTICE (loglevel: TRACE_NOTICE (5)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_WARNING (loglevel: TRACE_WARNING (4)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_ERR (loglevel: TRACE_ERR (3)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_CRIT (loglevel: TRACE_CRIT (2)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_ALERT (loglevel: TRACE_ALERT (1)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_EMERG (loglevel: TRACE_EMERG (0)) (type: tracepoint) lttng_ust_tracef:event (loglevel: TRACE_DEBUG (14)) (type: tracepoint) lttng_ust_lib:unload (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_lib:debug_link (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_lib:build_id (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_lib:load (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:end (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:procname (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:debug_link (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:build_id (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:bin_info (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:start (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) PID: 626 - Name: xz lttng_ust_libc:posix_memalign (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:memalign (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:realloc (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:calloc (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:free (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_libc:malloc (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_pthread:pthread_mutex_unlock (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_pthread:pthread_mutex_trylock (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_pthread:pthread_mutex_lock_acq (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_pthread:pthread_mutex_lock_req (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:dlclose (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:debug_link (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:build_id (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:dlmopen (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_dl:dlopen (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG (loglevel: TRACE_DEBUG (14)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_LINE (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_FUNCTION (loglevel: TRACE_DEBUG_FUNCTION (12)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_UNIT (loglevel: TRACE_DEBUG_UNIT (11)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_MODULE (loglevel: TRACE_DEBUG_MODULE (10)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_PROCESS (loglevel: TRACE_DEBUG_PROCESS (9)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_PROGRAM (loglevel: TRACE_DEBUG_PROGRAM (8)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_SYSTEM (loglevel: TRACE_DEBUG_SYSTEM (7)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_INFO (loglevel: TRACE_INFO (6)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_NOTICE (loglevel: TRACE_NOTICE (5)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_WARNING (loglevel: TRACE_WARNING (4)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_ERR (loglevel: TRACE_ERR (3)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_CRIT (loglevel: TRACE_CRIT (2)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_ALERT (loglevel: TRACE_ALERT (1)) (type: tracepoint) lttng_ust_tracelog:LTTNG_UST_TRACEPOINT_LOGLEVEL_EMERG (loglevel: TRACE_EMERG (0)) (type: tracepoint) lttng_ust_tracef:event (loglevel: TRACE_DEBUG (14)) (type: tracepoint) lttng_ust_lib:unload (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_lib:debug_link (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_lib:build_id (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_lib:load (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:end (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:procname (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:debug_link (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:build_id (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:bin_info (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) lttng_ust_statedump:start (loglevel: TRACE_DEBUG_LINE (13)) (type: tracepoint) I'm not sure why all this showed up 3 times. Could be because I have systemd unit file ExecStart calling a script so that my LD_PRELOAD= line can work. ExecStart= didn't like LD_PRELOAD. So now I'm guessing ... I haven't read the fine documentation far enough yet, that I have to somehow connect my record event rules to PID 601 somehow and I'm getting empty trace records cause I'm not smart enough (yet) to figure out how to do that. Hopefully I'm getting "warmer". Regards, Brian _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev