Chapter 18. Set Up Lock Striping

Lock Striping allocates locks from a shared collection of (fixed size) locks in the cache. Lock allocation is based on the hash code for each entry’s key. Lock Striping provides a highly scalable locking mechanism with fixed overhead. However, this comes at a cost of potentially unrelated entries being blocked by the same lock.

Lock Striping is disabled by default in Red Hat JBoss Data Grid. If lock striping remains disabled, a new lock is created for each entry. This alternative approach can provide greater concurrent throughput, but also results in additional memory usage, garbage collection churn, and other disadvantages.

Lock striping in Red Hat JBoss Data Grid’s Remote Client-Server mode is enabled by setting the striping element to true.

<locking acquire-timeout="20000"
	 concurrency-level="500"
	 striping="true" />

<locking acquire-timeout="20000"
	 concurrency-level="500"
	 striping="true" />

The locking element uses the following attributes:

Lock striping is disabled by default in Red Hat JBoss Data Grid. Configure lock striping in JBoss Data Grid’s Library mode using the striping parameter as demonstrated in the following procedure.

<local-cache>
		<locking concurrency-level="${VALUE}"
			 isolation="${LEVEL}"
			 acquire-timeout="${TIME}"
			 striping="${TRUE/FALSE}"
			 write-skew="${TRUE/FALSE}" />
</local-cache>

<local-cache>
		<locking concurrency-level="${VALUE}"
			 isolation="${LEVEL}"
			 acquire-timeout="${TIME}"
			 striping="${TRUE/FALSE}"
			 write-skew="${TRUE/FALSE}" />
</local-cache>