Bugzilla – Full Text Bug Listing
| Summary: | [DataBinding] MapDelegatingValueObservableMap performance problems | ||||||||
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| Product: | [Eclipse Project] Platform | Reporter: | przemyslaw.pelczar <przemyslaw.pelczar> | ||||||
| Component: | UI | Assignee: | Platform UI Triaged <platform-ui-triaged> | ||||||
| Status: | CLOSED WONTFIX | QA Contact: | |||||||
| Severity: | normal | ||||||||
| Priority: | P3 | CC: | przemyslaw.pelczar | ||||||
| Version: | 3.6 | ||||||||
| Target Milestone: | --- | ||||||||
| Hardware: | All | ||||||||
| OS: | All | ||||||||
| Whiteboard: | stalebug | ||||||||
| Attachments: |
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Created attachment 178536 [details]
call tree from profiler
Created attachment 178537 [details]
call tree - details of MapEntry.getValue
You can see that in MapDelegatingValueObservableMap.MapEntry.getValue invoking DecoratingObservableMap.containsKey() takes 99% of time because it's delegated to AbstractMap.containsKey(). On the other hand DecoratingObservableMap.get() is fast because its delegated to HashMap.get().
Sounds like a better solution is to override containsKey to use the HashMap method like get() is doing--no? I think you are right. Maybe SetDelegatingValueObservableMap and MapDelegatingValueObservableMap should override containsKey and use DelegatingCache cache property in it. I don't know details of implementation. But feel that case of null key in maps should be analysed to propose good solution. This bug hasn't had any activity in quite some time. Maybe the problem got resolved, was a duplicate of something else, or became less pressing for some reason - or maybe it's still relevant but just hasn't been looked at yet. If you have further information on the current state of the bug, please add it. The information can be, for example, that the problem still occurs, that you still want the feature, that more information is needed, or that the bug is (for whatever reason) no longer relevant. This bug hasn't had any activity in quite some time. Maybe the problem got resolved, was a duplicate of something else, or became less pressing for some reason - or maybe it's still relevant but just hasn't been looked at yet. As such, we're closing this bug. If you have further information on the current state of the bug, please add it and reopen this bug. The information can be, for example, that the problem still occurs, that you still want the feature, that more information is needed, or that the bug is (for whatever reason) no longer relevant. -- The automated Eclipse Genie. |
Build Identifier: 20100617-1415 MapDelegatingValueObservableMap uses IObservableMap.containsKey in MapEntry.getValue(), MapEntry.setValue() and put() methods. In most cases implementation of containsKey is AbstractMap (because AbstractObservableMap extends AbstractMap). This causes big performance problems, because AbstractMap.containsKey has linear complexity. Invoking AbstractMap.containsKey should be avoided. Happily MapEntry.getValue() can be changed to not use this method. Now is: public Object getValue() { getterCalled(); if (!masterMap.containsKey(key)) return null; Object masterValue = masterMap.get(key); return cache.get(masterValue); } Should be: public Object getValue() { getterCalled(); Object masterValue = masterMap.get(key); if (masterValue == null) { return null; } return cache.get(masterValue); } Now adding 1000 elements to WritableList binded to TableViewer using ViewerSupport causes about 500 000 invocations of SetDelegatingValueObservableMap.EntrySet.next() Reproducible: Always Steps to Reproduce: 1. Bind TableViewer with few columns to WritableList using ViewerSupport.bind 2. Try to add more that 1000 elements to WritableList.