The only mention I've found anywhere about using multiple web method instances is in this post: "If the web method VI is marked reentrant, than multiple requests can be handled concurrently (and your application logic should account for that fact). If the web method is not marked reentrant, than only one request at a time can call the VI and subsequent request threads will block waiting to be able to call your VI." darenw, talking about web services in 8.6. This makes plenty of sense and is what I expect. However, I find this not to be the case [using 2010 SP1]. My example is very simple: Make the web method VI consist only of a "Wait (ms)" function set to wait for 10000 ms [10 s]. Check the "reentrant execution" box in the VI Properties dialog. Add the web method VI to a RESTful Web Service build spec and build and deploy. Then type the URL for the web method into two browser windows and send both queries at close to the same time. The first window will take 10s waiting for a response before finishing, as expected. The second window will take 20s--apparently the second instance of the web method VI does not start running until the first instance is completed. Not only does this conflict the the quote above, but it's a poor behavior for web services in general [and it's fatal to my application in particular]. [To be complete I should add that running the web method VI in multiple parallel instances in the same container VI results in a 10s run as expected]. Is this a bug or what? [this is an appendage to this ongoing discussion but is distinct enough from the original topic that I decided it should get its own--I apologize for the clutter if that was the wrong decision]

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Alright, sorry about that--apparently at some point the reentrance property had been disabled. Oy.

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