A couple of days ago, I posted on how I was monitoring memory usage on a recently upgraded CF8 server. I was seeing a quite a bit of memory being tied up in the tenured generation portion of the JVM Heap that would steadily rise all day.
Since there were so many dramatic changes between ColdFusion MX 7 and ColdFusion 8, I wasn't sure if this really indeed was a "problem" or simple a difference in behavior. Afterall once the load on the server would reduce in the evening I'd see the tenured generation usage drop back down to an acceptable and more expected value.
Because this did have me concerned, I kept digging around server logs to see if I could find any clues to why I was seeing the memory usage climb. I then noticed that the ColdFusion8/runtime/logs/coldfusion-out.log files were getting tons and tons of activities. After opening up the log files, I noticed I had tons of errors like the following:
Adobe always seems to like releasing things to Adobe Labs in mass. They've also just released Flex Builder 3 (Public Beta 3). I actually found beta 2 to be pretty stable and have even rolled out a project into production based on beta 2. I plan on upgrading as soon as I have some time.
Adobe Labs just released BlazeDS as a new Open Source project (released under the LGPL v3 license.) Essentially BlazeDS is the remoting and messaging technology behind LiveCycle Data Services. For people familiar with Adobe Flex, they know that this is the "push" technology that allows you to build interfaces that are updated automatically when the data on the server changes. This means you can make data on the screen change in realtime as changes on the server occur.
I spent a few minutes looking through the BlazeDS documentation, but didn't see any real good information related specifically to ColdFusion. However, according to the Release Notes it looks like you can integrate BlazeDS directly with ColdFusion 8.
Yesterday, I posted on how to use JConsole to monitor ColdFusion's JVM. Today I wanted to give you a quirk and dirty script you can run on ColdFusion 8 which will give you a lot of the same memory information—but wrapped up into a CF script. The script is based on some code from Steve Brownlee's useful post on accessing ColdFusion internals using Java.
The key benefit to this method is there's nothing to install—just copy the code on a server and run it. Obviously, this only works if the server is responding and is not going to be as thorough as using JConsole. I have found this script handy to just give you a quick overview of the system state.
I've only tested the code in CF8, but it doesn't utilize any special ColdFusion classes—it utilizes the core Java classes. This code should work on any ColdFusion installation using Java 5 (v1.5) or higher.