Encoder resolution on fast turning shafts

[jbernardis]

We are planning on using an encoder on our shooter design to determine actual RPMs. Do I need to worry about interrupt load on the processor if I have the combination of a fast (~5000RPM) shaft and a high resolution encoder. I was thinking of trying to get a reduction gear in there to reduce the RPM and then go with a low res (32 ticks/rev) encoder.

Are the considerations the same if I connect the encoder to the Talon SRX instead of the Rio??