Tooz

Document page: https://docs.openstack.org/tooz/latest/

Tooz is a library to manage the distributed primitives like group membership protocol, lock service and leader election. It provides a common coordination API for different drivers, like zookeeper, redis, memcached, etcd, .etc.

Drivers

Document page: https://docs.openstack.org/tooz/latest/user/drivers.html

Zookeeper

The zookeeper is the reference implementation and provides the most solid features as it's possible to build a cluster of zookeeper servers that is resilient towards network partitions for example.

Considerations

Primitives are based on sessions (and typically require careful selection of session heartbeat periodicity and server side configuration of session expiry).

Redis

The redis driver is a basic implementation and provides reasonable resiliency when used with redis-sentinel. A lot of the features provided in tooz are based on timeout (heartbeats, locks, etc) so are less resilient than other backends.

Considerations

• Less resilient than other backends such as zookeeper.
• Primitives are often based on TTL(s) that may expire before being renewed.

Memcached

The memcached driver is a basic implementation and provides little resiliency, though it’s much simpler to setup. A lot of the features provided in tooz are based on timeout (heartbeats, locks, etc) so are less resilient than other backends.

Considerations

• Less resilient than other backends such as zookeeper and redis.
• Primitives are often based on TTL(s) that may expire before being renewed.
• Lacks certain primitives (compare and delete) so certain functionality is fragile and/or broken due to this.