[lttng-dev] Getting started with UST

Sun May 26 08:51:04 EDT 2013

Hi,
I'm trying to get UST working for the first time on RHEL 6.4.

I compiled and installed the following packages:
userspace-rcu-0.7.6
lttng-ust-2.1.2
lttng-tools-2.0.5
babeltrace-1.1.0

When I ran the sample app in lttng-ust/examples I couldn't see any traces.

# lttng create test_session
Session test_session created.
Traces will be written in /root/lttng-traces/test_session-20130526-071315

# lttng start
Tracing started for session test_session

# cd /usr/local/share/doc/lttng-ust/examples/gen-tp/

# make
lttng-gen-tp -o sample_tracepoint.h sample_tracepoint.tp
gcc  -c -o sample.o sample.c
lttng-gen-tp -o sample_tracepoint.c sample_tracepoint.tp
lttng-gen-tp -o sample_tracepoint.o sample_tracepoint.tp
gcc -o sample sample.o sample_tracepoint.o -ldl -llttng-ust
rm sample_tracepoint.c

# ./sample

# lttng stop
Tracing stopped for session test_session

# lttng view
Trace directory: /root/lttng-traces/test_session-20130526-071315

[error] Cannot open any trace for reading.

[error] opening trace
"/root/lttng-traces/test_session-20130526-071315" for reading.

[error] none of the specified trace paths could be opened.

# ls -l /root/lttng-traces/test_session-20130526-071315
total 0

What am I doing wrong? I attached the debug log from the lttng-sessiond.

Thanks,
Aryeh
-------------- next part --------------
# lttng-sessiond --verbose --no-kernel
DEBUG3: Creating LTTng run directory: /var/run/lttng [in create_lttng_rundir() at main.c:4325]
DEBUG1: Client socket path /var/run/lttng/client-lttng-sessiond [in main() at main.c:4617]
DEBUG1: Application socket path /var/run/lttng/apps-lttng-sessiond [in main() at main.c:4618]
DEBUG1: LTTng run directory path: /var/run/lttng [in main() at main.c:4619]
DEBUG3: Created hashtable size 4 at 0x24ce0a0 of type 1 [in lttng_ht_new() at hashtable.c:96]
DEBUG3: Created hashtable size 4 at 0x24ce340 of type 1 [in lttng_ht_new() at hashtable.c:96]
DEBUG1: Signal handler set for SIGTERM, SIGPIPE and SIGINT [in set_signal_handler() at main.c:4459]
Warning: No tracing group detected
DEBUG1: epoll set max size is 363581 [in compat_epoll_set_max_size() at compat-epoll.c:224]
DEBUG1: [thread] Manage application started [in thread_manage_apps() at main.c:1179]
DEBUG1: Apps thread polling on 2 fds [in thread_manage_apps() at main.c:1200]
DEBUG1: Thread manage kernel started [in thread_manage_kernel() at main.c:876]
DEBUG1: Updating kernel poll set [in update_kernel_poll() at main.c:748]
DEBUG1: Thread kernel polling on 2 fds [in thread_manage_kernel() at main.c:905]
DEBUG1: [thread] Manage application registration started [in thread_registration_apps() at main.c:1392]
DEBUG1: Notifying applications of session daemon state: 1 [in notify_ust_apps() at main.c:687]
DEBUG1: Got the wait shm fd 17 [in get_wait_shm() at shm.c:117]
DEBUG1: Futex wait update active 1 [in futex_wait_update() at futex.c:62]
DEBUG1: Accepting application registration [in thread_registration_apps() at main.c:1423]
DEBUG1: [thread] Dispatch UST command started [in thread_dispatch_ust_registration() at main.c:1324]
DEBUG1: Futex n to 1 prepare done [in futex_nto1_prepare() at futex.c:73]
DEBUG1: Woken up but nothing in the UST command queue [in thread_dispatch_ust_registration() at main.c:1334]
DEBUG1: [thread] Manage client started [in thread_manage_clients() at main.c:3802]
DEBUG1: Accepting client command ... [in thread_manage_clients() at main.c:3834]
DEBUG1: Wait for client response [in thread_manage_clients() at main.c:3871]
DEBUG1: Receiving data from client ... [in thread_manage_clients() at main.c:3906]
DEBUG1: Nothing recv() from client... continuing [in thread_manage_clients() at main.c:3910]
DEBUG1: Clean command context structure [in clean_command_ctx() at main.c:534]
DEBUG1: Accepting client command ... [in thread_manage_clients() at main.c:3834]
DEBUG1: Wait for client response [in thread_manage_clients() at main.c:3871]
DEBUG1: Receiving data from client ... [in thread_manage_clients() at main.c:3906]
DEBUG1: Processing client command 8 [in process_client_msg() at main.c:3317]
DEBUG3: mkdir() recursive /root/lttng-traces/test_session-20130526-071315 with mode 504 for uid 0 and gid 0 [in run_as_mkdir_recursive() at runas.c:339]
DEBUG1: Using run_as_clone [in run_as() at runas.c:323]
DEBUG1: Tracing session test_session created in /root/lttng-traces/test_session-20130526-071315 with ID 1 by UID 0 GID 0 [in session_create() at session.c:232]
DEBUG1: Sending response (size: 16, retcode: Success) [in thread_manage_clients() at main.c:3944]
DEBUG1: Clean command context structure [in clean_command_ctx() at main.c:534]
DEBUG1: Accepting client command ... [in thread_manage_clients() at main.c:3834]
DEBUG1: Wait for client response [in thread_manage_clients() at main.c:3871]
DEBUG1: Receiving data from client ... [in thread_manage_clients() at main.c:3906]
DEBUG1: Nothing recv() from client... continuing [in thread_manage_clients() at main.c:3910]
DEBUG1: Clean command context structure [in clean_command_ctx() at main.c:534]
DEBUG1: Accepting client command ... [in thread_manage_clients() at main.c:3834]
DEBUG1: Wait for client response [in thread_manage_clients() at main.c:3871]
DEBUG1: Receiving data from client ... [in thread_manage_clients() at main.c:3906]
DEBUG1: Processing client command 16 [in process_client_msg() at main.c:3317]
DEBUG1: Getting session test_session by name [in process_client_msg() at main.c:3372]
DEBUG1: Sending response (size: 16, retcode: Success) [in thread_manage_clients() at main.c:3944]
DEBUG1: Clean command context structure [in clean_command_ctx() at main.c:534]
DEBUG1: Accepting client command ... [in thread_manage_clients() at main.c:3834]
DEBUG1: UST registration received with pid:8433 ppid:25028 uid:0 gid:0 sock:18 name:sample (version 2.1) [in thread_registration_apps() at main.c:1510]
DEBUG1: Futex n to 1 wake done [in futex_nto1_wake() at futex.c:100]
DEBUG1: Accepting application registration [in thread_registration_apps() at main.c:1423]
DEBUG1: Futex n to 1 wait done [in futex_nto1_wait() at futex.c:87]
DEBUG1: Futex n to 1 prepare done [in futex_nto1_prepare() at futex.c:73]
DEBUG1: Dispatching UST registration pid:8433 ppid:25028 uid:0 gid:0 sock:18 name:sample (version 2.1) [in thread_dispatch_ust_registration() at main.c:1346]
DEBUG1: Woken up but nothing in the UST command queue [in thread_dispatch_ust_registration() at main.c:1334]
DEBUG3: Created hashtable size 4 at 0x7fdd6c0009d0 of type 1 [in lttng_ht_new() at hashtable.c:96]
DEBUG1: App registered with pid:8433 ppid:25028 uid:0 gid:0 sock:18 name:sample (version 2.1) [in ust_app_register() at ust-app.c:1365]
DEBUG1: Apps with sock 18 added to poll set [in thread_manage_apps() at main.c:1280]
DEBUG1: Apps thread polling on 3 fds [in thread_manage_apps() at main.c:1200]
DEBUG1: PID 8433 unregistering with sock 18 [in ust_app_unregister() at ust-app.c:1395]
DEBUG1: Apps thread polling on 2 fds [in thread_manage_apps() at main.c:1200]
DEBUG3: Call RCU deleting app PID 8433 [in delete_ust_app_rcu() at ust-app.c:237]
DEBUG1: Wait for client response [in thread_manage_clients() at main.c:3871]
DEBUG1: Receiving data from client ... [in thread_manage_clients() at main.c:3906]
DEBUG1: Nothing recv() from client... continuing [in thread_manage_clients() at main.c:3910]
DEBUG1: Clean command context structure [in clean_command_ctx() at main.c:534]
DEBUG1: Accepting client command ... [in thread_manage_clients() at main.c:3834]
DEBUG1: Wait for client response [in thread_manage_clients() at main.c:3871]
DEBUG1: Receiving data from client ... [in thread_manage_clients() at main.c:3906]
DEBUG1: Processing client command 17 [in process_client_msg() at main.c:3317]
DEBUG1: Getting session test_session by name [in process_client_msg() at main.c:3372]
DEBUG1: Sending response (size: 16, retcode: Success) [in thread_manage_clients() at main.c:3944]
DEBUG1: Clean command context structure [in clean_command_ctx() at main.c:534]
DEBUG1: Accepting client command ... [in thread_manage_clients() at main.c:3834]
DEBUG1: Wait for client response [in thread_manage_clients() at main.c:3871]
DEBUG1: Receiving data from client ... [in thread_manage_clients() at main.c:3906]
DEBUG1: Processing client command 13 [in process_client_msg() at main.c:3317]
DEBUG1: Counting number of available session for UID 0 GID 0 [in lttng_sessions_count() at main.c:2057]
DEBUG1: Getting all available session for UID 0 GID 0 [in list_lttng_sessions() at main.c:2084]
DEBUG1: Sending response (size: 4388, retcode: Success) [in thread_manage_clients() at main.c:3944]
DEBUG1: Clean command context structure [in clean_command_ctx() at main.c:534]
DEBUG1: Accepting client command ... [in thread_manage_clients() at main.c:3834]
DEBUG1: Wait for client response [in thread_manage_clients() at main.c:3871]
DEBUG1: Receiving data from client ... [in thread_manage_clients() at main.c:3906]
DEBUG1: Nothing recv() from client... continuing [in thread_manage_clients() at main.c:3910]
DEBUG1: Clean command context structure [in clean_command_ctx() at main.c:534]
DEBUG1: Accepting client command ... [in thread_manage_clients() at main.c:3834]
DEBUG1: Wait for client response [in thread_manage_clients() at main.c:3871]
DEBUG1: Receiving data from client ... [in thread_manage_clients() at main.c:3906]
DEBUG1: Processing client command 9 [in process_client_msg() at main.c:3317]
DEBUG1: Getting session test_session by name [in process_client_msg() at main.c:3372]
DEBUG3: No kernel session when tearing down session [in teardown_kernel_session() at main.c:363]
DEBUG3: No UST session when tearing down session [in teardown_ust_session() at main.c:390]
DEBUG1: Destroying session test_session [in session_destroy() at session.c:151]
DEBUG1: Sending response (size: 16, retcode: Success) [in thread_manage_clients() at main.c:3944]
DEBUG1: Clean command context structure [in clean_command_ctx() at main.c:534]
DEBUG1: Accepting client command ... [in thread_manage_clients() at main.c:3834]
DEBUG1: Updating kernel poll set [in update_kernel_poll() at main.c:748]
DEBUG1: Thread kernel polling on 2 fds [in thread_manage_kernel() at main.c:905]