Bug 182177

Summary:	[performance] JavaCore.newLibraryEntry() has very high invocation count on startup
Product:	[Eclipse Project] JDT	Reporter:	Michael Rennie <Michael_Rennie>
Component:	Debug	Assignee:	JDT-Debug-Inbox <jdt-debug-inbox>
Status:	RESOLVED WONTFIX	QA Contact:
Severity:	normal
Priority:	P3	CC:	darin.eclipse
Version:	3.3	Keywords:	performance
Target Milestone:	---
Hardware:	PC
OS:	Windows XP
Whiteboard:

Description Michael Rennie

2007-04-12 13:07:43 EDT

Following investigation into bug 179685 we found that JavaCore.newLibraryEntry() has a very high invocation count during startup when considering EEs with access rules - see profiling screen shots on 179685.

Comment 1 Jerome Lanneluc

2007-04-13 06:31:48 EDT

Michael, I'm not sure to understand what you expect from us. JDT/Debug is making all these invocations, isn't it ?

Comment 2 Michael Rennie

2007-04-13 10:10:20 EDT

yes we are, we were thinking (hoping) that there would be some way that we could batch or cache already created entries to be reused. Although as each access rule participant can create custom rules per project this seems unlikely.

Comment 3 Michael Rennie

2007-04-13 10:19:03 EDT

we'll take this one back, as it has to do with us not you guys :)

Comment 4 Michael Rennie

2007-04-13 12:38:11 EDT

The way the current API stands there is nothing we can do about this. 
To cache entries we need a compound key something like 
(vminstall, rules, environmentid) -> classpath entries

which would be sufficient, but each query to an EE for its rules creates a new array of rules (as the rules are collected from all of the participnats at the time the request for the rules occurs), therefore we can not effectively compare the arrays of rules for equality (using == ) without incurring more work than is already done. 

There is no way to batch create libraries.

marking as WONTFIX, since realistically there is nothing we can do....