Zope Object Database - Pluggable Storages

Pluggable Storages

• Network Storage (aka ZEO) - Enables multiple python processes load and store persistent instances concurrently.
• File Storage - Enables a single python process to talk to a file on disk.
• relstorage - Enables the persistence backing store to be a RDBMS.
• Directory Storage - Each persistent data is stored as a separate file on the filesystem. Similar to FSFS in Subversion.
• Demo Storage - An in-memory back end for the persistent store.
• BDBStorage - Which uses Berkeley DB back end. Now abandoned.

Failover Technologies:

• Zope Replication Services (ZRS) - A commercial add-on that removes the single point of failure, providing hot backup for writes and load-balancing for reads.
• zeoraid - An open source solution that provides a proxy Network Server that distributes object stores and recovery across a series of Network Servers.
• relstorage - since RDBMS technologies are used this obviates need for ZEO server.
• NEO - Distributed (fault tolerance, load-balancing) storage implementation.