> Now I am a complete Erlang novice, but I think OTP has (some kind of) > built-in support for system upgrades. It might be worth checking out > to see if there is something we can adapt to Clojure?
There are several tiers of reliability that determine what kinds of fixes/upgrades you can do. At low levels (2-3 nines) you can run with one machine and fix it as you go. At 4-5 nines, you use redundant machines (and georedundancy), and having a stable machine image is important for hardware swaps. You never fix on the server unless the alternative is dropping calls, and the customer is on the phone *right now*. (That's the worst environment to figure out a fix, of course.) Above that (6 nines) is the realm of ATC and telephony, where you might not be able to afford to bring a system down at all. Erlang/OTP was designed for this space, so it includes hot-swappable components, though you test and verify them beforehand! Re consistency: I seem to recall Pascal Costanza working on activation of layers, so you can swap a whole set of stuff across your program. He spoke about it at ILC2009, but I'm not sure I've found the right paper. Common Lisp-specific, though. -R --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -~----------~----~----~----~------~----~------~--~---
