Software AG Products 10.7 | Administering Integration Server | Configuring Ehcache on Integration Server | Configuring a Distributed Cache | The Nonstop Behavior of a Distributed Cache
 
The Nonstop Behavior of a Distributed Cache
The Enable High Availability parameter places a distributed cache in nonstop mode. Nonstop mode enables the Integration Server to take a prescribed action if an operation on the distributed cache does not complete within a specified timeout period (for example, if the Terracotta Server Array is unresponsive because it is busy or if the network connection is down).
When you create a distributed cache with the Integration Server Administrator, it automatically enables the Enable High Availability parameter. You cannot disable this option.
Because distributed caches on Integration Server operate in nonstop mode, you must configure the following parameters when you create a distributed cache. These parameters specify how long you want Integration Server to wait for a response from the Terracotta Server Array, and which steps you want it to take when a cache operation takes longer than the specified time.
Parameter
Description
Timeout
Specifies the amount of time (in milliseconds) that must elapse before Integration Server determines that it cannot reach the Terracotta Server Array and performs the time-out measure specified in Timeout Behavior.
Timeout Behavior
Specifies which of the following steps you want Integration Server to take in order to complete a cache operation when the Terracotta Server Array does not respond within the amount of time specified in Timeout.
*exception - Return a NonStopCacheException.
*noop - Return a null for “get” operations. Ignore operations that modify elements in the cache (for example, “put,” “replace,” and “remove” operations).
*localReads - Return elements that reside in the local cache in response to “get” operations. Ignore operations that modify elements in the cache (for example, “put,” “replace,” and “remove” operations).
Immediate Timeout When Disconnected
Specifies whether Integration Server should automatically time out all subsequent operations for this cache when Integration Server recognizes that it has become disconnected from the Terracotta Server Array.
If the Immediate Timeout When Disconnected option is enabled when Integration Server becomes disconnected, Integration Server immediately times out all subsequent operations on the cache and performs the time-out measure specified in Timeout Behavior. This option stops Integration Server from waiting for every operation to timeout when it is in the disconnected state. The Integration Server will begin processing cache operations normally again after it successfully rejoins the Terracotta Server Array.
For more information about the nonstop features of a distributed cache, see the BigMemory Max product documentation for 4.1 at www.terracotta.org/documentation.
For more information about setting these parameters on Integration Server, see Creating a Cache.