I red over ethash source code and saw this code:
func CreatePoW(config *Config) (pow.PoW, error) {
switch {
case config.PowFake:
glog.V(logger.Info).Infof("ethash used in fake mode")
return pow.PoW(core.FakePow{}), nil
case config.PowTest:
glog.V(logger.Info).Infof("ethash used in test mode")
return ethash.NewForTesting()
case config.PowShared:
glog.V(logger.Info).Infof("ethash used in shared mode")
return ethash.NewShared(), nil
default:
return ethash.New(), nil
}
}
What does shared mode mean? And when is ethash in shared mode?