plugin visu_websocket: extend protocol to enable cancellation of time series abonnement about plugins

[msinn]

How would the driver in smartVISU cancel a series and how would this functionality be used in smartVISU?

[bmxp]

Have a look at this post in knxuf

[bmxp]

Maybe we should also think about using threads for retrieving data, see this post in knxuf

[psilo909]

It could be that this problem passes through the whole core and to different plugins, e.g. database, which is also not multithreaded

[psilo909]

Also i think i remember there was a discussion about the performance of highcharts in some cases

[psilo909]

i just made a test at my setup:

i opened the page with the "outside temperatures" charts (3 lines, raw values, several charts up to 6 months in the past). in parallel i opened some historic data in the database plugin's webif. while the chart data is being queried in the database, i tried to reload the historic data in the webif. the page reload was stuck until the charts were loaded in smartvisu. so i think the bottleneck is the database is.

i think the only way to solve it would be to "merge" datapoints like the old sqlite plugin did ( think that is the reason why the "file based database" worked better als mentioned in the KNXUF thread) or to generate and use a more performant database scheme. currently all historic data is in one table only. even a multithreaded visu_websocket plugin wont help here much.

[msinn]

Cancelation of series is implemented in SmartHomeNG v1.7.2