[tor-relays] Bandwidth Spike

I'm a fairly new Tor relay operator and noticed something peculiar with my bandwidth for the relay recently. It seems to have jumped WAY up and just plateaued at what I have the peak bandwidth limit set at. Is there any kind of explanation for this? Is this normal behavior? Could it indicate some kind of denial of service attack?

Here's a screenshot I took of the bandwidth history: https://i.imgur.com/mRyKp9L.jpg (note that both R/W plateau at the same point in time)

Perhaps this is normal behavior but I want to know if it's something that might be messed up with my configuration that I can correct.

-Bryan