https://issues.apache.org/bugzilla/show_bug.cgi?id=52998
Bug #: 52998
Summary: Performance issue with ExpressionFactory.newInstance()
Product: Tomcat 7
Version: 7.0.26
Platform: PC
OS/Version: Windows XP
Status: NEW
Severity: normal
Priority: P2
Component: Jasper
AssignedTo: dev@tomcat.apache.org
ReportedBy: knst.koli...@gmail.com
Classification: Unclassified
javax.el.ExpressionFactory.newInstance() implementation in Tomcat 7 does not
cache created instance and performs class name discovery on every invocation.
The discovery process involves looking for the file named
"META-INF/services/javax.el.ExpressionFactory". So every invocation of the
method involves looking for and maybe reading the file.
This issue was reported on the dev list, see thread:
[1] "Two performance problems (found during myfaces testing)", starting on
2012-03-08,
- http://tomcat.markmail.org/thread/7bbvzmkvyvryvn44
- http://marc.info/?t=133124021200002&r=1&w=2
The above thread [1] also references this one of myfaces:
[2] "EL method invocation performance", 2010-08-25:
- http://www.mail-archive.com/dev@myfaces.apache.org/msg48482.html
------------------
My evaluation is that
1. This problem is specific for Tomcat 7. - The ExpressionFactory.newInstance()
method was added in EL 2.2 and Tomcat 6 does not have it.
2. It hits javax.el.BeanELResolver#invoke() the most, as
ExpressionFactory.newInstance() is called on each invocation.
3. There are 2 places where the factory instance is stored in a static field.
This is good for performance, but breaks the discovery process and may cause
consequences if implementation is bundled in a web application. It is a bug.
The places:
org.apache.jasper.runtime.JspApplicationContextImpl.expressionFactory
org.apache.jasper.compiler.Validator$ValidateVisitor.EXPRESSION_FACTORY
--
Configure bugmail: https://issues.apache.org/bugzilla/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org
For additional commands, e-mail: dev-h...@tomcat.apache.org
