1. Introduction
  2. TimesTen Architecture
  3. Database Processes

Database Processes

TimesTen initiates separate background processes to each database to perform operations:

TimesTen Daemon

The TimesTen daemon starts when TimesTen is installed. This main daemon runs in the background. The instance administrator must manually start and stop the daemon after each system reboot or the root user can start the daemon by running the daemon startup script.

The TimesTen daemon performs the following functions:

  • Manage shared memory access

  • Coordinate process recovery

  • Keep management statistics on what databases exist, which are in use, and which application processes are connected to which databases

  • Manage RAM policy

  • Start replication processes (if requested), the TimesTen Server and the cache agent (if enabled).

Application developers do not interact with the daemon directly. No application code runs in the daemon and application developers do not generally have to be concerned with it. Application programs that access TimesTen databases communicate with the daemon transparently using TimesTen internal routines.

See Working with the TimesTen Daemon in the Oracle TimesTen In-Memory Database Operations Guide.

Subdaemons

The main TimesTen daemon spawns subdaemons dynamically as they are needed.

TimesTen uses subdaemons to perform the following:

  • Manage databases

  • Flush the transaction log buffer to the file system

  • Perform periodic checkpoints in the background for the active database

  • Load the database into memory from a checkpoint file on the file system

  • Implement the data aging policies of various tables

  • Detect and handle deadlocks

  • Roll back transactions for abnormally terminated direct-mode applications

  • Perform required background processing for the database

  • Recover the database if it needs to be recovered after loading it into memory

See Managing Subdaemons in the Oracle TimesTen In-Memory Database Operations Guide.