Adding visible Y axis dramatically slows fastline series.

Anaesthesia · Post by **Anaesthesia** » Fri Jul 11, 2008 10:45 pm

I'm plotting waveform data every 5 msecs. If the Y axis is not visible a single CPU can handle it quite easily. If I make the Y axis visible, CPU usage approximately doubles. Is this a bug or a feature?

Many Thanks.

Narcís · Post by **Narcís** » Mon Jul 14, 2008 7:50 am

Hi Anaesthesia,

Could you please try setting axes as suggested in the Real-time charting article here and check if that improves your application performance?

Thanks in advance.

Anaesthesia · Post by **Anaesthesia** » Tue Jul 15, 2008 10:29 pm

Dear Narcis,

Thanks for your prompt reply. Doing what you say really doesn't do much. (Although not all the calls mentioned are available in the dotnet version.)

I'm not sure how to attach the images of CPU usage in order to show you, but basically on a dual quad-core xeon system running under XP with SP3, the thread uses over 90% of a single CPU's time when the axis is turned on and abou 50% when it is turned off.

The work-around is to draw the axis scales as a background image.

I hope this helps,

Yours Sincerely

Anaesthesia

Narcís · Post by **Narcís** » Wed Jul 16, 2008 9:51 am

Dear Anaesthesia,

You can post your files at news://www.steema.net/steema.public.attachments newsgroup or at our upload page.

It would be very helpful if you also send a simple example project we can run "as-is" to reproduce the problem here.

Thanks in advance.

Anaesthesia · Post by **Anaesthesia** » Fri Jul 18, 2008 5:02 am

Dear Narcis,

I've submitted the 2 files. When the axis is plotted the thread running in the 4th processor represents the plotting activity.

In contrast, when the axis is set to not visible, the thread activity is much less (the 8th processor).

I'll try and put together a demo. In essence I'm using a multimedia timer firing at a frequency of 50 Hz and plotting the result of the solution of some differential equations (which compute a pressure waveform).

Yours Sincerely,

Andy Pybus

Narcís · Post by **Narcís** » Fri Jul 18, 2008 7:34 am

Hi Andy,

Thanks for the images and information. Can you reproduce the issue using the All Features\Welcome !\Speed\Realtime charting example in the features demo, available at TeeChart's program group? It works fine for me here.

Thanks in advance.