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From: Tim Chase <python.list@tim.thechases.com>
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Subject: Re: Understanding Python from a PHP coder's perspective
Date: Mon, 7 Dec 2015 21:11:14 -0600
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On 2015-12-08 10:09, Chris Angelico wrote:
> All three are very different.
> 
> 1) Process state.
> 
> You start up a Python program, and it sits there waiting for a
> request. You give it a request, and get back a response; it goes
> back to waiting for a request. If you change a global variable, or
> maintain persistent state, or anything, the next request will 'see'
> that change. This is completely global.

1) This is completely global *to the process* (you can have multiple
Python processes sitting around waiting, taking advantage of multiple
cores)

2) This is almost always a bad idea for multiple reasons (it can get
in the way of scaling, it can produce hard-to-track-down bugs, etc).
Use a real session store (a database, a key/value store like
memcached, a NoSQL store like Redis, store session info in cookies,
etc.) instead.

-tkc