They rewrote a relatively small part of their code base, a small part of their in memory cache. For a team who a) wrote the code base and b) change it every day

They rewrote a relatively small part of their code base, a small part of their in memory cache. For a team who a) wrote the code base and b) change it every day, this wasn't a big deal more then it was an interesting problem. From an operations standpoint I'd consider app servers that need to be rotated every hour or so a very brittle architecture. (I don't let that kind of think go without protesting wildly.)