diff --git a/doc/devel/meeting_summary/2024-01-10.txt b/doc/devel/meeting_summary/2024-01-10.txt index feb1300fe..847e911b1 100644 --- a/doc/devel/meeting_summary/2024-01-10.txt +++ b/doc/devel/meeting_summary/2024-01-10.txt @@ -3,20 +3,20 @@ :Author: Benny :Date: 2024-01-20 -Jan 10, 2024 on #lumiera 20:00 - 23:00 UTC + +Jan 10, 2024 +on {l}/project/contact.html#_irc[`#lumiera`] +20:00 - 23:00 UTC + __Participants__ * ichthyo - * benny - - + * benn '''' - Two main points of discussion: - - Scheduler tests to examine its suitability - - Using Gstreamer to view video for our verttical slice + + - Scheduler tests to examine its suitability + - Using Gstreamer to view video for our vertical slice Test Scheduler Suitability @@ -28,57 +28,60 @@ provide information on performance limitations so that we would be able to estab whether these limitations met the demands required by Lumiera. Results were encouraging. -_Ichthyo_ reported on stress tests on the new scheduler. With over 500 test -jobs the scheduler was stable. Stress tests revealed typical limitations of -the scheduler, which exhibited behaviour that is well within the requirements -oof Lumiera. Load tests showed that the sheduler remained stable when -subjected to heavy loads. +_Ichthyo_ reported on stress tests on the new scheduler. After resolving a series +of initial bugs, processing runs stable now, even when entering over 500 test jobs +simultaneously to the queue. Stress tests revealed typical limitations of the scheduler, +which exhibited behaviour that is well within the requirements of Lumiera. Load tests +showed that the scheduler remained stable when subjected to short heavy load bursts +within expected bounds. -Stress tests wrere somewhat more involved as it was necessary -to establish reasonable performance boundaries of the scheduler: we can always -overload any scheduler with -fanatically huge numbers of jobs so that beyond its abaility to process all jobs on the -queue. Indeed scheduler performace is always a delicate and complex area to -investigate. Of interest, however, is to establish some reasonable information -on the processing rate of the schedular which -_Ichthyo_ was able to estimate statistically by carefully observing the -scheduler under a collection of various loads. +Indeed performance testing is always a delicate and complex area to +investigate, as it is necessary to establish reasonable performance boundaries +of the system: we can always overload any scheduler with fanatically huge numbers +of jobs; while the scheduler is still able to process all enqueued jobs eventually, +congestion builds up and jobs start missing their deadlines. Of interest, however, +is to establish some reasonable information on the processing rate of the scheduler +which _Ichthyo_ was able to estimate statistically by carefully observing the +scheduler under a collection of pre-calibrated loads. Some goals of the tests: - - tests to establish the scheduler breaking point or performance limitations - - tests under pressure with high loads and high parallelism - - test to demonstrate that the scheduler is stable under load for several seconds + - establish the scheduler breaking point or performance limitations + - tests under pressure with parallelism and complex dependencies between jobs + - demonstrate that the scheduler is stable under typical load for several seconds -Tests on various hardware constellations are not expected to reveal any -unexpected information. - -Tests will not ultimately resolve the issue of whether the scheduler can perform -as desired, but by carefully selecting the kind of tests to subject the -scheduler to can reduce the probility of unexpected performance bottleneck. +Tests on a wider array of hardware constellations are not expected to reveal much +relevant information in this stage of the project and will thus be conducted later. +This kind of analytical, isolated component tests will not ultimately resolve the +issue of whether the scheduler can perform as desired, but subjecting the scheduler +to carefully selected tests can help to reduce the probability of missing serious +performance limitations inherent to the chosen design. GStreamer Demo to Play Video ---------------------------- _Benn_ has written a simple GStreamer demo so that a video in raw format can be -displayed on the GUI for the current vertical slice. Should the output be directly -played in some widget, or is it better to load the pixels into some -buffer in memory which can then be displayed by some other mechanism. +displayed on the GUI for the current vertical slice. The next step in this +investigation is to identify a low-level entrance point to the functionality +provided by the GStreamer library, since for use in this vertical slice the +render engine produces a buffer filled with raw video data for each frame, +which will then be displayed in a video widget as an ongoing process. -This is a general question requiring further investigation: play a video -directly or supply the raw data directly in some buffer? +This is a general question requiring further investigation: how to make use of +established functionality from a library to simplify our implementation task, +while retaining the full control and coordination of the rendering and playback +process and resource management within the Lumiera render engine itself. '''' Next meeting ------------ -The next Lumiera meeting is scheduled for Wednesday, Feb 17 at 20:00 UTC. +The next Lumiera meeting is scheduled for Wednesday, Feb 14 at 20:00 UTC. Should this be inconvenient for you, please speak up on, for example, link:http://lists.lumiera.org/cgi-bin/mailman/listinfo/lumiera[lumiera@lists.lumiera.org] and let us know of when you would prefer to attend. '''' - diff --git a/doc/devel/meeting_summary/index.txt b/doc/devel/meeting_summary/index.txt index 8ec1a4ab8..ecd045ea3 100644 --- a/doc/devel/meeting_summary/index.txt +++ b/doc/devel/meeting_summary/index.txt @@ -11,6 +11,19 @@ spending time on the task of writing a summary. Anyone interested in Lumiera development is also encouraged to read mailing list archives and other documentation. +10 Jan 2024 +----------- + +Topics +~~~~~~ + * Scheduler performance testing + * using GStreamer for Video output to the GUI + +Summary +^^^^^^^ + * link:2024-01-10.html[Summary (by benn)] + + 13 Dec 2023 -----------