What I meant is whether it is possible to do something like this: There are trace point events A, B, C, D in the source; Alice wants to run a tracing session with A and B enabled, Bob wants to run a tracing session with C and D enabled. The two sessions should be able to happen concurrently.
Is it supported with sessiond (lttng-tools addition) or no? If yes, unsure how the current interface allows for it (my misunderstanding of the interface?) Thanx, -----Original Message----- From: Irina Guilman Sent: May 26, 2011 5:22 PM To: 'David Goulet'; Amer Alhalabi Cc: Leyla Kinaze; Anik Mishra; [email protected]; Jim Dumont; Jean Junior Adelson Subject: RE: [ltt-dev] Session Daemon - Listing Events Thanx! David, ready? :) Now bombarding you with questions... 1) lttng_ust_start_trace(pid_t pid) starts tracing for a particular pid. How do i set the session to which the trace will belong? 2) Suppose <pid> is being traced in 2 concurrent sessions. With the call lttng_ust_stop_trace(pid_t pid) it stops tracing for this process for which session? 3) What is a relationship between session names and ids? Suppose I create a new session lttng_ust_start_trace(pid_t pid). Will an id be assigned to it automatically and then I just ask for an id or do I explicitely assign id to it? 4) lttng_ust_list_apps(pid_t **pids) lists processes which are currently running and which are instrumented? (ie have markers, trace point events, etc.) 5) What does char *lttng_get_readable_code(int code) do? 6) Which concurrent session support currently exists? -----Original Message----- From: David Goulet [mailto:[email protected]] Sent: May 26, 2011 4:04 PM To: Amer Alhalabi Cc: Leyla Kinaze; Anik Mishra; [email protected]; Jim Dumont; Jean Junior Adelson Subject: Re: [ltt-dev] Session Daemon - Listing Events Comments below: On 11-05-26 03:45 PM, Amer Alhalabi wrote: > Hi All, > I have a few questions regarding the Session Daemon. > 1. Is it possible to list all available events for a given PID? Not yet. > 2. Is it possible to list all enabled events for a given PID? Not yet. > 3. If the answer to above is Yes, could you please give me with the > signutures of those functions (if you have them)? The goal is to move "libustctl" from the UST git tree to lttng-tools tree and use that API to do all user-space tracing commands. Those functions interacting with the user-space tracer are in the lttng-tools git tree at "ltt-sessiond/ust-ctl.c". However, for now, there is none for listing events/markers. > 4. I looked at the current version of Userspace Tracer-UST but I did > not find those functionalities although list-trace-events for a given > PID was available in an older version. Is that work still in progress? Normally, "list-markers" should give you all markers or/and tracepoints and the state (0: disable, 1: enable). "list-trace-events" is only to list "TRACE_EVENT" which are not yet fully implemented and right now are only dummy printf. As soon as UST is modified to support the new session daemon (of lttng-tools repo), listing events for a given PID will be available upon the UST release. Don't hesitate for any other questions. Cheers! David > Thanks a lot in advance for your help! > Amer > > > > *AMER ALHALABI * > *Software Developer* > > Ericsson Canada Inc. > Common Components > 8500 Decarie Blvd > H4P 2N2, Mount Royal, QC, Canada > Phone +1 514 345-7900 ext. 43082 > [email protected] > _www.ericsson.com_ > > > <http://www.ericsson.com/> > > This Communication is Confidential. We only send and receive email on > the basis of the terms set out at _www.ericsson.com/email_disclaimer_ > <http://www.ericsson.com/email_disclaimer> > > > > _______________________________________________ > ltt-dev mailing list > [email protected] > http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev -- David Goulet LTTng project, DORSAL Lab. PGP/GPG : 1024D/16BD8563 BE3C 672B 9331 9796 291A 14C6 4AF7 C14B 16BD 8563 _______________________________________________ ltt-dev mailing list [email protected] http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev _______________________________________________ ltt-dev mailing list [email protected] http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
