How does the getblocktemplate request rate correlate with a miner's hashrate?

[Geremia]

What is the relationship between a miner's hashrate and the getblocktemplate (GBT) request rate?

^{(The question "How does the rate of getwork requests correlate with the hashrate of a miner?" discusses getwork, but that's outdated.)}

(cf. the related Bitcoin StackExchange question)

[-ck]

It makes absolutely no difference to the hashrate since work generation is done on the miner. The frequency of getblocktemplate requests correlates with the amount of transactions you are likely to include from the current set of transactions. The more frequently you do it, the more transactions on average you will have. It is the pool/pool software that determines the frequency of GBT requests. Stratum stipulates updates should occur every minute and usually the pool software will have an updated set of transactions along with each stratum update, but there is nothing stopping the pool from just sending the old set of transactions every minute. Most pools send out a new set of transactions every minute; p2pool does not, usually waiting longer, and ckpool defaults to doing it every 30 seconds which is why the ckpool instances out there have more transactions on average (it also NEVER generates transaction free work templates).