Dts.Variables Collection, Threading, And Contention

All,

We are experiencing some problems when running the same package on multiple threads of a C# application concurrently. The package instances seem to share a Dts.Variables collection.

I have created a test application and package to reproduce the issue. The package is very simple. It has two variables - Instance (Int32) and Content (string). The test application runs two concurrent threads that run through 25 iterations running the package. Each thread loads the package, sets the instance, and then runs the package. The package then takes the instance, sticks it in the Content variable and then writes it to a file called "FileX" where X is the Instance. Thread 1 sets the instance from 1 to 25, thread 2 sets it from 26 to 50. The test execution results in about 15% of the files containing the incorrect "instance content". That is, I'll see "42" in the file named "File14", or something along those lines. This tells me that the variables are being overwritten.

I ran another test where I created a copy of the package, so the code is identical, but the VersionGUID is different. Running the thread test application always succeeds. There is no file name/content mismatch. I then ran another test where I manually edit the XML of the package to change the VersionGUID before the package is loaded (by calling LoadFromXml). Again this never fails.

Changing the VersionGUID may work for us, but it is a total hack. Has anyone else experienced this or have any other solutions? Any thoughts on manually updating the VersionGUID to get around this problem? I hate doing this, but we are getting desperate.

Thanks in advance,

Rob