tracker issue : CF-4169991

Problem Description:

If a CFC is stored in Session, its reference to coldfusion.runtime.NeoPageContext prevents pageContext's response from being garbage collected.

Steps to Reproduce:

1. Enable JMX on CF instance - http://boncode.blogspot.ca/2010/04/cf-java-using-free-visualvm-tool-to.html
2. Enable SessionManagement in Application.cfc
3. Prepare an empty Foo.cfc component (e.g. component {} )
4. Hit this following script with Apache JMeter for 1000 times:

<cfset session.foo = new Foo()>
<cfoutput><cfloop from=1 to="100000" index="i" >#rand()# </cfloop></cfoutput>


Actual Result:

ColdFusion will eventually run out of heap because the large page buffer (1,048,600bytes) cannot be garbage collected.

By inspecting Heap Dump in Visual VM, sort by size (descending) in Classes:
1. Double click the first one, which should be `byte[]`
2. In the left Instances panel, sort by Size (descending)
3. Locate one of the repeating instance with size ~1,048,600 bytes, right click, show Nearest GC Root

this     - value: byte[] #1
 <- buf     - class: coldfusion.runtime.CachedBufferedOutputStream, value: byte[] #1
  <- outstr     - class: coldfusion.tagext.io.cache.ehcache.GenericResponseWrapper, value: coldfusion.runtime.CachedBufferedOutputStream #324
   <- response     - class: coldfusion.jsp.JspWriterIncludeResponse, value: coldfusion.tagext.io.cache.ehcache.GenericResponseWrapper #324
    <- response     - class: coldfusion.runtime.NeoPageContext, value: coldfusion.jsp.JspWriterIncludeResponse #1
     <- pageContext     - class: cfFoo2ecfc175958891, value: coldfusion.runtime.NeoPageContext #324
      <- filterChain     - class: coldfusion.runtime.TemplateProxy, value: cfFoo2ecfc175958891 #323
       <- value     - class: java.util.HashMap$Node, value: coldfusion.runtime.TemplateProxy #324
        <- [7]     - class: java.util.HashMap$Node[], value: java.util.HashMap$Node #77122
         <- table     - class: java.util.HashMap, value: java.util.HashMap$Node[] #8314
          <- map     - class: coldfusion.util.FastHashtable, value: java.util.HashMap #8360
           <- mTable     - class: coldfusion.runtime.MemorySessionScope, value: coldfusion.util.FastHashtable #640
            <- value     - class: java.util.Hashtable$Entry, value: coldfusion.runtime.MemorySessionScope #323
             <- [1]     - class: java.util.Hashtable$Entry[], value: java.util.Hashtable$Entry #12973
              <- table     - class: java.util.Hashtable, value: java.util.Hashtable$Entry[] #1527
               <- value     - class: java.util.Hashtable$Entry, value: java.util.Hashtable #1437
                <- [36]     - class: java.util.Hashtable$Entry[], value: java.util.Hashtable$Entry #12972
                 <- table     - class: java.util.Hashtable, value: java.util.Hashtable$Entry[] #1537
                  <- mSessionPool     - class: coldfusion.runtime.SessionTracker, value: java.util.Hashtable #853
                   <- [6934]     - class: java.lang.Object[], value: coldfusion.runtime.SessionTracker class SessionTracker
                    <- elementData     - class: java.util.Vector, value: java.lang.Object[] #10332
                     <- classes     - class: coldfusion.bootstrap.BootstrapClassLoader, value: java.util.Vector #86
                      <- contextClassLoader (thread object)     - class: org.quartz.simpl.SimpleThreadPool$WorkerThread, value: coldfusion.bootstrap.BootstrapClassLoader #1


Expected Result:

ColdFusion should not have a hard reference to the page buffer and the buffer should be garbage collected to free up the heap.


Any Workarounds:

Do not store CFC in session, or lower session timeout to as short as possible.

----------------------------- Additional Watson Details -----------------------------

Watson Bug ID:	4169991

External Customer Info:
External Company:  
External Customer Name: Henry Ho
External Customer Email:  
External Test Config: Server Details



Server Product	ColdFusion

Version	11,0,09,299201

Tomcat Version	7.0.68.0

Edition	Developer  

Operating System	Windows 10  

OS Version	10.0  

Update Level	C:/ColdFusion11/test/lib/updates/chf11000009.jar  

Adobe Driver Version	5.1.3 (Build 000094)  



JVM Details



Java Version	1.8.0_92  

Java Vendor	Oracle Corporation  

Java Vendor URL	http://java.oracle.com/

Java Home	C:\Program Files\Java\jdk1.8.0_92\jre  

Java File Encoding	Cp1252  

Java Default Locale	en_US  

File Separator	\  

Path Separator	;  

Line Separator	Chr(13)

User Name	henryho  

User Home	C:\Users\henryho  

User Dir	C:\ColdFusion11\test\bin  

Java VM Specification Version	1.8  

Java VM Specification Vendor	Oracle Corporation  

Java VM Specification Name	Java Virtual Machine Specification  

Java VM Version	25.92-b14  

Java VM Vendor	Oracle Corporation  

Java VM Name	Java HotSpot(TM) 64-Bit Server VM  

Java Specification Version	1.8  

Java Specification Vendor	Oracle Corporation  

Java Specification Name	Java Platform API Specification  

Java Class Version	52.0

Attachments:

1. July 01, 2016 00:00:00: 1_Capture.PNG
2. July 01, 2016 00:00:00: 2_testcase.zip

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