My Moto X randomly started lagging heavily. It's unbearable.
It's not just a little bit here and there, the entire system is EXTREMELY LAGGY. It takes 30 seconds for the device to register a touch or perform an action.
I have root + stock ROM + gravitybox + very minimal third-party apps.
What the hell is going on?
Many things could cause it. Backgrounded app crashing over and over (loop), malware (very unlikely), weird software conflicts, perhaps you froze an app that the system is trying to wake non stop, etc. Might be faster just to backup, RSDlite and restore. Titanium Backup and Ultimate Backup make it very easy with batch backups/restore. 2 key inputs backs up all your apps and 2 restores them lol. It's ridiculously easy
Also make sure you're not running battery saving mode, I imagine that caps your max clock speed to a lower value although it shouldn't cause THAT big of a performance hit.
Apps like BetterBattery stats or GSAM can also show you what's hammering your battery in the background and occupying your CPU cycles. I would take a quick peak at those tools first before I decide how to approach the situation.
What's happening is some app or software conflict is polling (sending commands to) your CPU non stop so when you interact with your phone each key press/swipe/action is put into what is now a long queue for the CPU to process it. Kind of like a lineup at a coffee shop in the morning, you wanna get in and out fast but they gotta serve the people in front of you first.