Community
Participate
Working Groups
Created attachment 185499 [details] Trace file For the attached trace file, LTTV reports a lot more state transitions than the ones displayed by the CFV for the process ./open-write (pid = 570). It seems that the Eclipse kernel state system fails to associate quite a lot of events to this pid. This is also what the SV shows. To reproduce: - Load the attached trace in Eclipse - Load the same trace in LTTV - Compare CFVs for pid = 570 - Compare SVs
This is the original posting from the mailing list: http://dev.eclipse.org/mhonarc/lists/linuxtools-dev/msg00681.html
I investigated the problem and here are my findings: Control Flow View (CFV): ------------------------ In the Control Flow View, the user can step through the currently displayed events using the next/previous event buttons. The CFV doesn't store all events in the displayed time range, to save heap memory. The number of events displayed depends on the time range, window size and screen resolution. So, when stepping, only the currently in the CFV stored events are considered. In the CFV, the non-displayed events are marked with dotted line. To be able to step through all available events, the user needs to zoom until all events are displayed in the current time range (no dotted lines). Conclusion: The Eclipse kernel state system is considering all events and no events are missing. By zooming, all events can be accessed through the CFV. Statistics View (SV): --------------------- There are two processes with the same PID, parent PID and "birth" time, but with different process name: bash and ./open-write (PID 570). Basically, these two refer to the same process. The name is changed from bash to ./open-write only when fs.exec is executed. The SV, counts statistics, amongst others, based on the process name. In LTTV, this distinction based on the process name is not done and that's why the statistics for the process ./open-write is different to the Eclipse based SV.
I changed the importance of the bug to "normal" since all events can be accessed by zooming in the CFV. (see comment 2 below). A improvement is currently considered, that the user of the Eclipse CFV will be notified, when the user needs to zoom for more details. For the statistics view part of this bug, a new bug with ID 333114 was created. Any follow-up related to the statistic view will be done under bug 333114.
(In reply to comment #3) > I changed the importance of the bug to "normal" since all events can be > accessed by zooming in the CFV. (see comment 2 below). I tried doing this and it's not at all intuitive. Normal behaviour would be that you click previous and next and it just works. I understand that memory constraints dictate limiting the number of events, but there should be a way to make this work as expecting. After you have zoomed in to consume more events, do you then need to zoom out, move to a new time period and then zoom in again?
(In reply to comment #4) > > After you have zoomed in to consume more events, do you then need to zoom out, > move to a new time period and then zoom in again? You would need to zoom out only if you want to visualize a larger time range. If you want to keep the same resolution and visualize events out of the current time range, you can simply click and drag left/right the Gantt chart to slide the current time range window. There was a problem when zooming in which has been recently fixed (see bug https://bugs.eclipse.org/bugs/show_bug.cgi?id=333486). You get this fix you need to upgrade your eclipse to latest nightly build.
Fixed with bug 378402 with implementation of new Control Flow view for LTTng 2.0. Released in 1.0.
Removed incorrect dependency from bug 310629.
