1.  Intro

How well does JBossCache perform?  This is a question a lot of people have asked us.  This is just a start, but hopefully this page will grow to contain a wealth of knowledge on the performance characteristics of JBossCache.

See RunningPerformanceTestsOnJBossCache

2.  About the tests

The characteristics of each test are as follows:

• 3 test cases are run:

• 50PercentRead - 50% of the accesses are gets while 50% are puts.

• 75PercentRead - 75% of the accesses are gets while 25% are puts.

• 90PercentRead - 90% of the accesses are gets while 10% are puts.

• Each test case is run in 2 different modes:

• Single-node tests read and write to the same node in the TreeCache.

• Multi-node tests read and write to different nodes in the TreeCache.

• All caches use FIFOPolicy as an EvictionPolicy, with the following settings:

• maxNodes = 2000

• ttlSeconds = 600

• wakeupIntervalSeconds = 10

• Tests are run using 10 concurrent worker threads, each one looping through the test 100,000 times to arrive at 1,000,000 iterations per test before averages are calculated.

• Tests conducted on RHEL 3/2.4 Kernel, 2 x 3.06 GHz P4 Xeon CPUs, 2 GB RAM, using Sun JDK1.5.0_05

• All times measured are in milliseconds, to perform 100 operations.  E.g., a figure of 12.5 would mean 0.125 millis per operation.

• JBoss JRunit was used to measure benchmarks.

3.  Local caches

This section attempts to compare JBossCache running as a local cache (i.e., non-replicated).  Here, we compare the following caches tested:

1. Plain HashMap

2. JBossCache with Pessimistic locking (default), and Isolation Level set to NONE

3. JBossCache with Pessimistic locking (default), and Isolation Level set to REPEATABLE_READ (default)

4. JBossCache with Optimistic locking (experimental)

Note that some of the tests are skipped for certain caches tested:

• Multi-node is skipped when using a HashMap, since HashMaps have no concept of 'nodes'.

• Single-node is skipped when using Optimistically locked caches, since this will always result in transaction rollbacks (locks are held on a node level).