problem description
you want to use sphinx"s UpdateAttributes to do some immediate property update scenarios.
after updating with this method, you need to wait for the time set by attr_flush_period before the index persists to disk before it takes effect.
question: official documents and other people"s projects are set for a long time, such as 900. will there be any performance problems if attr_flush_period is set for a short time, such as 1 second or 10 seconds?