[jbossseam-issues] [JBoss JIRA] Commented: (JBSEAM-4244) fix for JBSEAM-4131 introduced a performance regression

[Riccardo Serafin (JIRA)]

    [ https://jira.jboss.org/jira/browse/JBSEAM-4244?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12472228#action_12472228 ] 

Riccardo Serafin commented on JBSEAM-4244:
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From: http://www.seamframework.org/Community/212PerformanceRegressionInMessages

The problem is the following: I've been profiling my application and since I switched to 2.1.2 I've noticed a huge amount of calls to Messages.AbstractMap.entrySet() and the related performance problem, as this method creates the entry set recurring all entries of all entry sets of the underlying properties maps. As a result, I get this method as the first one in the profiler in terms of consumed time.

After looking at the code, I noticed that: 

1) the implementation of containsKey that was included in 2.1.1 has been removed. This implementation used the faster get() method instead of the slower entrySet() method, which is used by the default AbstractMap implementation, to determine if the key is present.

2) The method resolveInMap in the SeamELResolver is now using a call to containsKey before trying to access the value.

So, to test if my theory was correct, I've replaced the Messages class with my own, which extends the default one and adds the containsKey implementation copied from 2.1.1. Profiling results has gone back to "normal".

To test, I guess you can just try to profile the execution of a containsKey on the current implementation, then put back the previous containsKey override and profile again. You should be noticing the gain. 

Related issues:
JBSEAM-2192 - This is the one where the containsKey fix was introduced.

JBSEAM-3916 - This is the one where the call to containsKey as been introduced in SeamELResolver (which worsen the problems).




> fix for JBSEAM-4131 introduced a performance regression
> -------------------------------------------------------
>
>                 Key: JBSEAM-4244
>                 URL: https://jira.jboss.org/jira/browse/JBSEAM-4244
>             Project: Seam
>          Issue Type: Bug
>          Components: Core
>            Reporter: Pete Muir
>            Assignee: Norman Richards
>             Fix For: 2.2.0.CR1
>
>


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