TCP/IP library very slow in CVI 7.0 vs CVI 6.0 ?

[pweihcel]

Hi !

We experience that the CVI 7.0 runtime DLL is way slower than CVI 6.0 when it comes to TCP/IP communication.

I have a program compiled with CVI 6.0 running fairly fast using TCP/IP library, but when compiling same program with CVI 7.0 using newer runtime engine the TCP/IP communication are very slow.
Up to 30-40 times slower responses (before like 3msec now 100msec).

Any suggestions ?

B.Rgds

Peter Weichel
Tellabs Denmark A/S

[bilalD]

Do you have a sample or some code snippet I could use to reproduce this effect on my machine? You really should not be seeing it slow down by this much. Are you running the same applications on the same machine? Is the tcp client application talking to another windows application or is this a custom device? What are the specs of the PC where you are using this?

Is the overall application slower or are you seeing that the tcp read functions don't return immediately? If you have a sample project with just tcp that you can use to reproduce the problem, please attach that here and we can investigate this further.

Thanks

[pweihcel]

Hi!

Well i could perhaps get some sample code, but it´s not related to just one program.

We use several programs which has connection to a CVI server on a target system, and uses TCP/IP to communicate with the PC GUI. The exact same program runs "normal speed" when the PC has installed Runtime Engine from CVI version 6, but if installing a program build in CVI 7 the runtime are replaced on the system (as we include that installation in the distribution kit), and after this the original version 6 build program AND the new version 7 build are acting much slower over the TCP/IP line.

Note this test is done using just one program running at the time, i.e. only one GUI talking TCP/IP to a CVI server on our target system.

I would think you can easily see the same behaviour using the TCP/IP demo programs.

B.Rgds
Peter Weichel

[bilalD]

Is the delay more evident when talking using TCP across a network or does it still occur if everything is happening on the localhost? approximately how much data are you transferring between client server using the tcp API? Im going to try to reproduce this here, so as much information as you can give me helps

Thanks