Enabling AnzoGraph Persistence

By default, Anzo manages the data in AnzoGraph by automatically reloading graphmart data into memory any time you restart AnzoGraph. Users have the option, however, to enable AnzoGraph's save data to disk option where AnzoGraph saves the data in memory to disk after every transaction. Each time AnzoGraph is restarted, the persisted data is automatically loaded back into memory.

This topic provides instructions for enabling AnzoGraph persistence.

Important Considerations

Before enabling persistence, consider the following important notes:

  • In general, each AnzoGraph server needs access to about twice as much disk space as RAM on the server. By default, AnzoGraph saves data to the install_path/persistence directory on the local file system. You can also configure AnzoGraph to save data to a mounted file system. For more information, see Relocating AnzoGraph Directories.
  • Persisted data is unique to each AnzoGraph version and cannot be re-used after an upgrade. If you upgrade AnzoGraph and persistence is enabled, the database will not start until it is reinitialized to remove the persisted data. See Reinitializing the Database for instructions.
  • When persistence is enabled, transactional workloads that perform many concurrent write operations may experience a performance degradation due to the overhead of writing the data from each transaction to disk.

Enabling Persistence

Follow the steps below to enable the AnzoGraph save to disk option.

  1. Stop the database.
  2. On the leader node, open the AnzoGraph settings file, settings.conf, in a text editor. The file is in the install_path/config directory.
  3. In settings.conf, find the following line in the file:
    enable_persistence=false
  4. Change the enable_persistence value to true:
    enable_persistence=true
  5. Save and close settings.conf.
  6. Restart the database to apply the configuration change.

After each transaction, AnzoGraph saves the data in memory to disk in the location specified in the persistence_directory setting.

Note To avoid unnecessary reloads, make sure that the AnzoGraph connection in Anzo is configured to enable the Use AnzoGraph persistence if available option. See Connecting to AnzoGraph for more information.
Related Topics