Designed and architected by technology visionary James Gosling in the mid-1990s, Java is a very popular programming language that has been adopted by many software developers. Programs written in Java are used today on millions of devices worldwide.
Java is the buzzword today everywhere.
Google's Android phones are a key factor and, while Android dominates the smartphone industry, Java is increasingly used in home appliances like televisions, refrigerators, dishwashers, and security systems. Java is an important technology driving the explosive growth of the Internet, especially smart devices and the 'Internet of Things'. Keep counting the number of computers and devices that use Java as the list is growing day by day.
Java's rapid adoption and growth cannot be attributed only to Android. Java can be easily ported to a wide variety of operating systems and platforms. Java can be used in Web applications, mobile apps, and complex user interface (UI) programs. Java can be used to integrate divergent legacy applications in extract-transfer-load (ETL) scenarios.
With so many Java programs all around us, it is important to manage and monitor existing and emerging Java-based applications.
What is Argent for Java?
Argent for Java is a comprehensive tracking, monitoring, and management solution focused on Java-based applications across your enterprise.
Argent for Java provides a rule-based monitoring engine that collects statistics and metrics about your Java applications and reports and generates alerts for exception conditions.
Why Argent for Java?
Although Java has been ported and migrated to many operating systems and platforms, the language and run time performance is rarely optimized for each particular platform. Independent Software Providers (ISPs) and IT departments are often most concerned about delivering application features and functionality as a priority ahead of performance and reliability.
The performance and reliability of Java-based applications vary widely and are not consistent. A Java application developed for a UNIX platform may perform poorly on a Windows platform (and vice versa).
Tracking, monitoring, and managing your Java-based applications' performance and resource utilization is critically important, especially in non-stop environments such as customer-facing website applications.
Monitoring CPU and memory utilization can provide useful information but does not help you relate that information to your Java applications.
Argent for Java makes monitoring and managing your Java applications both easy and efficient. With Argent for Java you can forget about memory leaks, deadlocked and blocked threads, CPU overload, and more.
Argent for Java helps ensure your Java-based applications perform smoothly and reliably across your entire enterprise.
Argent for Java screens both JVMs and base servers via Java Management Extensions (JMX) technology.
The Java Virtual Machine (JVM)
Java incorporates a design architecture called the Java Virtual Machine (JVM). The JVM is a hypervisor that executes the Java programs written for it. An implementation of the JVM is part of making Java available on a given platform and operating system. Without an implementation of the JVM, Java programs can not run. Java programs running within the JVM provide platform independence. This is because JVM converts the Java program's commands to the native language of the machine or device where the JVM and the Java program are installed.
When a Java application is launched, a JVM is instantiated for that application and persists in memory until the application completes. Internally, within a given operating system, there will be as many JVMs as there are Java applications launched.
Under Microsoft Windows, this is comparable to running a console-style application within a DOS command prompt window: There will be as many DOS command prompt windows as there are console-style command line programs active.
Since a JVM is a run-time environment for a Java application, each JVM will consume computer resources such as memory, CPU, and so on.
Argent for Java provides collects vital statistics for the JVM (and, correspondingly, the companion Java application).
Metrics and statistics collected include: Memory and CPU usage, CPU time consumed, thread and handle usage, thread counts, locks/deadlocks, and many more.
Argent for Java also keeps track of similar metrics for host machine where the JVM has been instantiated.
Within an instantiated JVM, memory must be allocated for new objects. Each JVM divides memory allocation into two categories: Heap Memory and Non-Heap Memory.
Java heap memory from the Operating System is allocated by the JVM and it manages the heap for its Java Application. Every time the Java application creates a new object, the Java Virtual Machine gives out an adjacent space or an array of heap memory to store it within the heap memory already it took from the OS. "Live" objects that are frequently referenced by other objects are retained in the heap and those not referenced anymore are emptied from the heap or Garbage Collected by the JVM. This frees the heap memory.
The most newly created objects are referred to as "Young" generation by JVM algorithms and they become "Old" generation after they endure a few garbage collection processes. The young generation holds on to a small but extremely active segment of the heap where new objects are allocated. When the space allocated for Young generation gets full, a special garbage collection called 'young collection' frees up some of the young heaps by moving or promoting the oldest of the "Young" heaps to the "Old" heap. This frees up some space in Young heap which lets the JVM to allocate new objects again. 'Old collection' frees up space in the old heap by running a garbage collection in the old heap.
Young generation heap is again split into Eden Space and Survivor Space.