>Having more CPU [cores], RAM, and IO is not going to solve for the need to shard your Redis, which is bound by a single core
But they chose redis in the first place as part of their messy, crummy pile of barely working junkware solution. You wouldn't use redis in the first place if you were building a solution that scales up.
So, now we also have to assume per-core software and support licenses to accompany our purchase of several $10M racks? What platform are we talking about now? Presumably I have to also purchase the IDE and toolchain licenses, per developer, too?
Twitter may have and will still make missteps, but you're being egregiously vague and unhelpful. Your comments are as vaporous as you make Twitter's architecture to be.