Abstract: Techniques are disclosed that pertain to a database system having a log owner and log tailers. The log owner maintains a transaction log and the log tailers replay the transaction log. A log tailer may receive a set of requests to perform a database transaction that involves a write operation to write a record and a subsequent read operation to read that record. As a part of performing the transaction, the log tailer may issue a request to the log owner to log the write operation in the transaction log and the log tailer may insert the record into a local memory structure of the log tailer. After receiving a response from the log owner that the write operation has been logged, the log tailer may permit the subsequent read operation to access the record from the local memory structure without requesting the record from the log owner.

Abstract: Techniques are disclosed relating to controlling the ordering of a set of processes executing as part of a distributed computing system on different execution nodes of a computer system. A computer system may track status information relating to execution of the set of processes. The computer system receives a call from a process indicating that the process has reached a code breakpoint. The computer system updates the status information to indicate that the process is in a blocked state and is waiting to be scheduled by the control server. The computer system deterministically selects, from a group of the set of processes that are in the blocked state, a particular process executing on a particular execution node to be executed next in a serial execution order. The computer system responds to a call from the particular process by indicating that the particular process is to unblock and resume execution.