Block size and transaction per block in Hyperledger Fabric

Question

What is the relationship between MaxMessageCount, AbsoluteMaxBytes, and PreferredMaxBytes?

A block in fabric consists of a MaxMessageCount number of transactions or PreferredMaxBytes?

What should be the value of these to get maximum throughput?

Answer 1

To understand the difference, we should first try and understand what these terms mean individually. 

MaxMessageCount is the maximum number of transactions that are permitted in a block. 

AbsoluteMaxBytes are the maximum number of bytes that are allowed for serialized transactions in a block. 

PreferredMaxBytes are the preferred number of bytes that are allowed for serialized transactions in a batch. When a transaction is larger than the PreferredMaxBytes, a larger batch will be formed. 

If there are numerous transactions then stuff as many transactions as possible in a block to get the maximum throughput. Otherwise, you can tweak the BatchTimeout and MaxMessageCount for optimizing overall transaction throughput.