I moved my Tor exit relay from my main server to a dedicated Raspberry Pi a week or two ago, and while it seemed to run fine at first it's been crashing a lot lately.
I made the heartbeat more frequent and checked the logs, and it looks like after a reboot the relay runs fine with ~150 open circuits for about 12 hours, then suddenly jumps up to 600 open circuits, prints a bunch of Your computer is too slow to handle this many circuit creation requests!
errors and then crashes.
I tried overclocking the Pi, upping the MaxOnionsPending to 250, and reducing the MaxAdvertisedBandwidth to 250KB, and none of those seemed to help. An email thread I saw speculated that this happens "when your relay becomes the hidden service directory, or introduction point, for a popular hidden service."
Does anyone have any ideas how to fix this? People who are running relays on Raspberry Pis, have you seen this or know how to deal with it?