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by astine 4427 days ago
I'll stipulate that you might want to be very conservative about doing this with a production system.

No kidding. I knew at least one guy who hosed a product launch by doing that. You even have to restart your development instance from time to time to make sure that your application state remains consistent. I've been scared to try, but I suspect that you could live-patch a server though if you were systematic about it and tested the patch ahead of time.
2 comments
Zak 4427 days ago
You even have to restart your development instance from time to time to make sure that your application state remains consistent.

There are ways around that. Stuart Sierra uses a scheme wherein the entire application is treated as a value, which can be re-generated on the fly. Of course, that's not terribly different in practice from restarting the whole environment, but it's faster and more convenient.

http://thinkrelevance.com/blog/2013/06/04/clojure-workflow-r...

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stcredzero 4427 days ago
Back in 2001, We had a corner case bug in our ORM that impacted a scheduled demo. So I connected with the live Smalltalk app server and changed the state of the DB locks during the demo.

There are technologies deigned to enable live updates. VisualWorks Smalltalk had one, though it was not widely used. There are real time OS that can update the kernel without going down.

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