TChart 5.0pro crash while adding points over long time

[rettichfoerster]

Hello,

we use a dynamic created TChart 5.0 pro in Delphi 7. Also tried the TChart 8 Eval.
If we add a new data point cyclic to chart (every second with timer event) the application crashes after 2 or 3 days (sometimes earlier) with "EStackOverflow".
Its important to keep the whole data in chart, so we just add new points without clearing. Unfortunately the amount of data or duration of adding points is variable.

Anyone have experience with such problem or better question: its possible to add points over long time this way at all?

Michael

[Narcís]

Hi Michael,

If you add data continuously to the chart without clearing it you'll end up running out of memory in the computer. Does it occur quicker in lower memory machines? It would be good if you could remove data as in the Real-time charting article here. An alternative would be reducing the number of points plotted in the chart using the DownSampling function as in the All Features\Welcome!\Functions\Extended\Reducing number of points example in the features demo, available at TeeChart's program group. However, the DownSampling function would mean having the source series data in memory and then the function series so probably this would speed up the chart but increase memory consumption as well.

[rettichfoerster]

Hello Narcís,

thanks for quick response.
the application exe only have a little increase of memory usage in windows task manager over time... the highest value i noticed was 180mb of memory after 3 days, but thats lesser i would expect for a out of memory crash. nevertheless, after all i think the only way is a rebuild to show a shifted part of measure data using AddArray.

Michael

[Narcís]

Hi Michael,

Thanks for your feedback. If the problem persists please attach a simple example project we can run "as-is" to reproduce the problem here.

Also tried the TChart 8 Eval.

Current TeeChart version is number 9 (aka 2011). Have you tried that one? Could you reproduce the problem there?

Thanks in advance.

[rettichfoerster]

Hello,

yesterday i prepared a complete new project for simple example with latest tchart eval. release for posting here. the funny thing, it seems to be working.
after that i tried to do a little "stress test" with 18 dynamic created charts and 7 series per chart. as last step i sped up the timer event cycle to 100ms for adding random points in every charts and series with AddXY. This also works proper.

again i noticed a little increase of memory usage and continous increase of cpu load (starts with 20% and end around 95% after 20 mintes runtime) but i guess its a normal behavior for such an amount of data and quick update cycle without clearing charts.

in my original project i have 16 charts with much lesser series than the new project have. even the timer event cycle is slower: 1s.
(when i also speed up the timer event to 100ms here the application crashes in under 15 minutes)

my problem is now. anyway, it seems that tchart cause the crashes. after commenting out all AddXY lines the application work fine over longtime. thats why we thought it was an issue adding points with tchart.

any suggestions?

Michael

[Yeray]

Hi Michael,

Have you tried the new testing application in TeeChart v5 too? It would be nice if we could take a look at this testing application if it still reproduces the problem in the latest release most of all.

However, if the problem isn't reproducible in the actual version, I'd suggest you to upgrade to it.