Hi John, Are these questions related to some contribution?
Sincerely, Dmitriy Pavlov ср, 8 авг. 2018 г. в 3:18, John Wilson <sami.hailu...@gmail.com>: > Hi, > > Assume the following: > > > - I have a transaction coordinator and two primary nodes with 0 backup > nodes. > - Persistence store is enabled. > - I'm running a transaction in pessimistic mode with serializable > isolation. > > I have these questions: > > 1. What exactly happens during the prepare phase? Only acquiring locks > on the two primary nodes? Or do the primary nodes themselves, in > addition > to acquiring locks, write to their respective WAL a TxRecord with a > "begin > prepare" info? > 2. Assume locks have been acquired successfully, would the nodes then > write a "prepared" TxRecord to WAL before returning a "Yes" vote to > coordinator? > 3. When the coordinator sends a commit message, would each node write > the key-values to the DataRecord and a commit to the TxRecord before > returning to coordinator? > > > Overall, I'm trying to understand what happens exactly during prepare and > commit phases and when the key-values involved in the transaction are > actually written; as well as the exact updates that are written to the WAL > files in each phase. > > appreciate your response. > > Thanks, >
