18.2.2. Unscheduled Write-Behind Strategy Configuration (Remote Client-Server Mode)

Procedure 18.2. The write-behind Element

1. The modification-queue-size Parameter

   The modification-queue-size parameter sets the modification queue size for the asynchronous store. If updates occur faster than the cache store can process the queue, the asynchronous store behaves like a synchronous store. The store behavior remains synchronous and blocks elements until the queue is able to accept them, after which the store behavior becomes asynchronous again.

   <file-store passivation="false" 
               path="${PATH}" 
               purge="true" 
               shared="false">
       <write-behind modification-queue-size="1024" />
   

2. The shutdown-timeout Parameter

   The shutdown-timeout parameter specifies the time in milliseconds after which the cache store is shut down. When the store is stopped some modifications may still need to be applied. Setting a large timeout value will reduce the chance of data loss. The default value for this parameter is 25000.

   <file-store passivation="false" 
               path="${PATH}" 
               purge="true" 
               shared="false">
       <write-behind modification-queue-size="1024" 
                     shutdown-timeout="25000" />
   

3. The flush-lock-timeout Parameter

   The flush-lock-timeout parameter specifies the time (in milliseconds) to acquire the lock that guards the state to be periodically flushed. The default value for this parameter is 15000.

   <file-store passivation="false" 
               path="${PATH}" 
               purge="true" 
               shared="false">
       <write-behind modification-queue-size="1024" 
                     shutdown-timeout="25000"  
                     flush-lock-timeout="15000" />
   

4. The thread-pool-size Parameter

   The thread-pool-size parameter specifies the size of the thread pool. The threads in this thread pool apply modifications to the cache store. The default value for this parameter is 5.

   <file-store passivation="false" 
               path="${PATH}" 
               purge="true" 
               shared="false">
       <write-behind modification-queue-size="1024" 
                     shutdown-timeout="25000"  
                     flush-lock-timeout="15000" 
                     thread-pool-size="5" />
   </file-store>