I am not sure what you are are asking. Are you asking for the rationale of why tornado was chosen as the basis of the Bokeh server? Or are you asking when or why a user would want to use the server, as opposed to creating standalone Bokeh documents?
If the former, we needed asynchronous IO, websockets, and python 2/3 support. Those requirements together narrow the set of possibilities fairly conclusively.
If the latter, there is a discussion of purpose and use case scenarios in the users guide:
On Apr 27, 2016, at 11:15 AM, [email protected] wrote:
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