My PS4 records continuously and stores up to 15 minutes - and I doubt it's all stored in RAM (although it's not impossible).Ok. Before I found it'd only be ~200 MB I thought that maybe it'd be continously writing to storage, which I thought was going to wear a hole through it pretty quickly (rewriting that same 200 MB for an hour means you've written to it... 240 times.
Another option is to just store the data needed to re-render the past 15 minutes. But that'd require the game engine to be written to support that.My PS4 records continuously and stores up to 15 minutes - and I doubt it's all stored in RAM (although it's not impossible).