[Web-SIG] PEP 444 feature request - Futures executor

[Timothy Farrell]

----- Original Message -----
From: "P.J. Eby" <pje at telecommunity.com>
To: "Timothy Farrell" <tfarrell at owassobible.org>, web-sig at python.org
Sent: Friday, January 7, 2011 2:14:20 PM
Subject: Re: [Web-SIG] PEP 444 feature request - Futures executor

> There are some other issues that might need to be addressed, like 
> maybe adding an attribute or two for the level of reliability 
> guaranteed by the executor, or allowing the app to request a given 
> reliability level.  Specifically, it might be important to distinguish between:

> * this will be run exactly once as long as the server doesn't crash
> * this will eventually be run once, even if the server suffers a 
> fatal error between now and then

> IOW, to indicate whether the thing being done is "transactional", so to speak.

I understand why this would be good (credit card transactions particularly), but how would this play our in the real world?  All servers will do their best to run the jobs given them.  

Are you suggesting that there would be a property of the executor that would change based on the load of the server or some other metric?  Say the server has 100 queued jobs and only 2 worker threads, would it then have a way of saying, "I'll get to this eventually, but I'm pretty swamped."?

Is that what you're getting at or something more like database transactions..."I guarantee that I won't stop halfway through this process."

Thanks,
-t