Hi, See https://github.com/lttng/lttng-tools/commit/c876d657fb08a91ca7c907b92f1b7604aee664ee .
We would appreciate your feedback on this if possible based on your use case. Cheers On Mon, May 03, 2021 at 05:05:10PM -0700, Eqbal via lttng-dev wrote: > Hi, > > I have a lttng live session trace consumer application using libbabeltrace2 > where I create a graph to consume lttng live session traces and output to > another sink. I am running the graph in a loop at some polling interval as > long as I get BT_GRAPH_RUN_STATUS_AGAIN status. What I am noticing is that > if my polling interval is large enough I tend to lose either all or some of > the events. I experimented with various polling intervals and it seems if > the polling interval is less than *DELAYUS *from "lttng-create > --live=DELAYUS" option then I am able to get all the events, otherwise I > tend to lose events. > > Here are the steps I follow: > 1. start session daemon and relay daemon > 2. create a live session (with default delay of 1s), enable events and start > 3. Start my application (hello world example from lttng docs) > 4. Start the consumer application built using libbabeltrace that connects > to the live session > > I noticed that the events are actually persisted in the ~/lttng-traces by > the relay daemon, but it does not reach babeltrace consumer application. I > have noticed the same behavior with babeltrace2 cli. > > I would like to understand what is the reason for such behavior and if > playing with the polling interval in relation to the DELAYUS value is the > right thing to do. > > Thanks, > Eqbal > _______________________________________________ > lttng-dev mailing list > lttng-dev@lists.lttng.org > https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev -- Jonathan Rajotte-Julien EfficiOS _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
