Extranonce It’s feature used to participate on mining big blocks, more than it’s a feature it’s optional to participate on mining big blocks or not to participate on mining big blocks, and by the mean of big blocks is the blockchain’s heavy blocks with more than 20 transactions. The feature optional and by default it’s turned off for safety purposes cause participating on the extranonce mining feature consume more energy and cause mining rig’s to heat extensively, but it can be turned on with configuration option #xnsub or on some programs #exnsub.
Extranonce
