Odd TCP/IP problem running under Windows-VMWare

[PhotonDemon]

Hi,

I'm seeing an odd TCP/IP problem running under Windows under VMWare. The programs that are having the problem are built with VAST 5.5.2 and Totally Objects SocketSet. It is possible that this is my bug but at this point I don't think so. The programs run on many other machines that are not under VMWare and all work fine.

The problem most often occurs between a GUI program that connects to an NT service. The GUI connects to the service and sends it short messages and the service does small jobs and sends replies. This works great everywhere but under VMWare. Under VMWare, it works for a while and then the connection times out. Sometime the server times out and sometimes the GUI times out. Both these programs are using very little CPU time. An action in the GUI will work and then the same action will get no response and time out.

If anyone has any idea at all as to what is going on here, I would love to hear it.

Lou

[PhotonDemon]

I have finally resolved this problem. First it wasn't really a TCP/IP problem. For this application, I normally run my VAST GUI programs that connect to my VAST servers that run as an NT service at a higher than normal Windows priority. This is because these GUI programs are often run on the server with the NT services and running them at a higher priority gives them better responsiveness. If they are run off the server on a workstation the higher priority isn't needed by doesn't hurt.

Well, running the GUIs at a higher priority under Windows under VMWare seems to interfere with the dispatching (I'm not sure at what level, VMWare or Windows) of the NT service program. The server doesn't get dispatched for many seconds and by the time it does TCP/IP connections have timed out. The very simple circumvention is to run the GUIs at normal Windows priority.

Lou

[wembley]

Lou -

I don't know if you've really found the source of your problem or not. This sounds very similar to a long-standing problem I (and others) have had on VMWare with the connection to a remote manager. VMWare, for some reason yet unknown to me, decides to reset the TCPIP connection (you can see this as a VMWare pop-up showing that a connection has been established). When this happens, the connection to the manager is lost (very annoying).

[PhotonDemon]

Hi John,

I'm sure the problem I have been having was caused by running the GUIs at a higher than normal Windows priority, because the problem went away when I run them at normal priority.

That doesn't mean that I'm not also seeing the problem you describe. If I am, it is infrequent and my code reconnects and moves on. Fortunately, the load on this site is low enough that if the problem is there, it doesn't matter much.

Thanks anyway for the heads up.

Lou