Overview of Space Attributes and Policies
The attributes of a space define the space’s behavior an mode of deployment.
By calling the SpaceDef functions or methods provided in the ActiveSpaces API, you can specify:
- Space Distribution
- Specifies whether a space is distributed.
For information on space distribution, see Distribution.
- Space Capacity
- Specifies the maximum number of entries per seeder.
- Eviction Policy
- (If a space capacity setting is specified, must be specified to set an eviction policy that is followed when the space capacity limit is reached.
- Replication Count
- Specifies whether replication is enabled, and if replication is enabled, specifies the number of seeders that are used to replicate data.
For information on replication, see Replication.
- Replication Type
- If replication is enabled, specifies whether replication is synchronous or asynchronous.
For information on synchronous and asynchronous replication, see Synchronous and Asynchronous Replication.
- Persistence
- Specifies whether space data is persisted to permanent storage, and if so, what type of persistence is used.
For information on persistence, seeSpace Storage Options and Persistence.
- Routing
- Specifies whether the space is routed.
For information on implementing routing for a space, see ActiveSpaces Routing
- Entry TTL
- Controls how long a tuple can remain unmodifed before it is evicted from the space.
For information on time to live and lock wait, see Expiration Time to Live and Tuple Locking.
- Lock TTL
- controls how long a tuple remains locked after an application has locked it.
For information on time to live and lock wait, see Expiration Time to Live and Tuple Locking.
- Lock Wait
- How long an operation attempting to modify a locked tuple can block while waiting for a tuple lock to clear.
For information on time to live and lock wait, see Expiration Time to Live and Tuple Locking.