From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel.Thibault@drdc-rddc.gc.ca (Thibault, Daniel) Date: Fri, 15 Nov 2013 20:22:34 +0000 Subject: [lttng-dev] =?iso-8859-1?q?=5BRELEASE=5D_LTTng-Tools_2=2E4=2E0-rc?= =?iso-8859-1?q?1_-_=C9poque_Opaque?= Message-ID: <48CF5AC71E61DB46B70D0F388054EFFD267A2503@VAL-E-01.valcartier.drdc-rddc.gc.ca> -----Message d'origine----- Date: Fri, 15 Nov 2013 12:27:01 -0500 From: David Goulet > 1) Live support. It's now possible to stream traces (kernel and UST) > while they being extracted meaning a relayd can now receive traces live > and a viewer can attach to it to process the trace while running. The > "--live" has been added to lttng create command that sets up a live > tracing session. > > See doc/live-reading-howto.txt and doc/live-reading-protocol.txt for > more detail on that feature. Does this mean you can't do a "live" trace to local storage? > 2) Java Util Logging support. With a special LTTngAgent located in > lttng-ust project (liblttng-ust-jul) to trace JUL events and gather UST > traces with them. > > The -j/--jul domain has been added to lttng command line so you can list > the possible JUL Logger object and enable/disable them. It is the same > as using the UST or Kernel domain. > > As of now, filters and loglevel are ignored with the JUL domain. Saying "It is the same as using the UST or Kernel domain" leaves a lot of questions unanswered, since the kernel and user-space behave *very* differently on a lot of points. 1) Does --jul require root privileges? 2) I suppose the various commands have --kernel pre-empting --userspace pre-empting --ul? 3) add-context: does --jul have the same possible context types as --userspace (i.e. ip, pthread_id, procname, vpid, vtid)? 4) enable-channel: 4.1) Are the --jul --subbuf-size, --num-subbuf and --read-timer defaults the same as with --userspace? 4.2) Presumably --output can only be mmap? 4.3) Are the --jul buffering schemes the same as with --userspace (i.e. --buffers-pid and --buffers-uid)? 4.4) If yes, won't they all degenerate to the virtual machine's user and process IDs? 5) enable-event: 5.1) Can you assign --jul events to multiple channels like you can in --userspace? 5.2) Is the --jul event type --tracepoint or something else entirely? 5.3) Can the trailing wild card (and exclusion option) be used in the event name when enabling/disabling --jul events? 6) list: Does bug #654 also apply to --jul? Daniel U. Thibault Protection des syst?mes et contremesures (PSC) | Systems Protection & Countermeasures (SPC) Cyber s?curit? pour les missions essentielles (CME) | Mission Critical Cyber Security (MCCS) R & D pour la d?fense Canada - Valcartier (RDDC Valcartier) | Defence R&D Canada - Valcartier (DRDC Valcartier) 2459 route de la Bravoure Qu?bec QC G3J 1X5 CANADA Vox : (418) 844-4000 x4245 Fax : (418) 844-4538 NAC : 918V QSDJ Gouvernement du Canada | Government of Canada