Ah, thank you, that makes more sense. Does that mean that the client intentionally throttles the stake mining thread? Otherwise I would expect to see at least one thread at 100% if you have any coins that are 30 days or older that haven't been staked yet.
Is there a command in ppcoind that can give me confirmation that it is trying to stake mine?
The stake minter thread is automatically running as long as the client wallet is running. If it couldn't run (e.g. locked wallet) it would give a message.
Normally it shouldn't consume much cpu when it is minting.