[WICKET-2741] non-performant Collections.synchronizedMap() should be replaced with ConcurrentMap

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.4.6
• Fix Version/s: 1.4.9, 1.5-M1
• Component/s: wicket
• Labels: performance
• Assignee: Igor Vaynberg
• Reporter: Nikita Tovstoles
• Created: 12/Feb/10 23:54
• Updated: 18/May/10 22:08
• Resolved: 17/May/10 21:23

Description

The following two classes use Collections.synchronizedMap() --> lots of contention @ concurrent load.

• RequestListenerInterface.interfaces
• WebApplication.addBufferedResponse
• Injector.inject() - 'cache' field.

The last instance makes @SpringBean unusable in production (too much contention @ concurrent load)

Here's a sample output of contention around monitor of class java.util.Collections$SynchronizedMap:

+--------------------------------------------------------------------------------------+------------------+-----------------+
|                                         Name                                         |    Time (ms)     |      Count      |
+--------------------------------------------------------------------------------------+------------------+-----------------+
|  +---java.util.Collections$SynchronizedMap.get(Object)                               |  126,101   51 %  |  19,145   52 %  |
|  | |                                                                                 |                  |                 |
|  | +---org.apache.wicket.injection.Injector.inject(Object, IFieldValueFactory)       |  109,912   45 %  |  16,285   44 %  |
|  | |                                                                                 |                  |                 |
|  | +---org.springframework.beans.CachedIntrospectionResults.forClass(Class)          |   16,188    7 %  |   2,860    8 %  |
|  |                                                                                   |                  |                 |
|  +---java.util.Collections$SynchronizedMap.put(Object, Object)                       |  119,343   49 %  |  17,676   48 %  |
|    |                                                                                 |                  |                 |
|    +---org.apache.wicket.injection.Injector.inject(Object, IFieldValueFactory)       |                  |                 |
|      |                                                                               |                  |                 |
|      +---org.apache.wicket.injection.ConfigurableInjector.inject(Object)             |                  |                 |
|        |                                                                             |                  |                 |
|        +---org.apache.wicket.injection.ComponentInjector.onInstantiation(Component)  |  118,060   48 %  |  17,467   47 %  |
|        |                                                                             |                  |                 |
|        +---com.castanealabs.gui.model.ZipCodeValidator.<init>()                      |      686    0 %  |     106    0 %  |
|        |                                                                             |                  |                 |
|        +---com.castanealabs.gui.model.ProductSkuProgramDataProvider.<init>(IModel)   |      337    0 %  |      59    0 %  |
|        |                                                                             |                  |                 |
|        +---com.castanealabs.gui.model.ProductTypeProgramDataProvider.<init>(IModel)  |      259    0 %  |      44    0 %  |
+--------------------------------------------------------------------------------------+------------------+-----------------+

Generated by YourKit Java Profiler 8.0.22 Feb 12, 2010 3:52:25 PM

Issue Links

• is duplicated by: WICKET-2875 Heavily Broken Caching in Injector