Will nuraft do batching ?

[Steamgjk]

Hi, @greensky00
Just want to confirm, when we followers receive more than 1 request from leader, or when leader has more than 1 request to send to followers, will it send one by one, or will it batch them into one, and then send?

[greensky00]

@Steamgjk
It does batching.

NuRaft/include/libnuraft/raft_params.hxx

Lines 389 to 393 in b1f7c07

	/**
	* Max number of logs that can be packed in a RPC
	* for append entry request.
	*/
	int32 max_append_size_;

[Steamgjk]

@greensky00
The default value is 100.
If I only submit 1 request, will the request be sent immeidately, or will it wait for a timeout, or until it has accumulated 100 requests (I think it is not this case)? I mean, there are expected to be at least two conditions that can trigger an RPC. The first one is to reach the batch size, and the second one is to reach a timeout. So what is the timeout length?

[greensky00]

@Steamgjk
If the connection to a follower is idle, the request is sent immediately. If the previous request is in flight, the next requests are sent as soon as it gets a response to the previous request. In that case, the next batch size will be min(number of pending requests, max_append_size_). There is no such threshold on timing or size.