Disruptor: Gating Sequence

Question

I am studying Disruptor in Java. I do not understand what's meaning of gating sequence. I know it core part is ring buffer and every buffer is associated with a sequence number.

Answer 1

Actually the core part of LMAX's implementation is the Sequencer and its Sequences. And so the ringBuffer implement those. The gatingSequences that you are referring to act as a cursor to each Sequencer that is "Subscribed" to the targeted ringBuffer (or other Sequencer). So that's how a Sequencer can have multiple cursors for its connected Sequencers (and let them touch the next sequence by just calling tryNext() ).

Cheers!

Answer 2

The purpose of gating sequences is to gate publishers to prevent the RingBuffer from wrapping.