Rails App Excessive Disk Read/Write

Rails App Excessive Disk Read/Write

a rails app that's been running in production for almost a year began
excessive disk read/writes after a push we did today.
Here's a read total graph.
As well as a read ops graph
We pushed at around 22:30 and disk usage went bananas.
If I'm doing the calculations right, we're writing 476m of data every few
minutes?
500000000 / 1024 / 1024 = 476.83
Either way, I'm unsure where to begin looking. Some help would be
appreciated.