java method profiling

not improve efficiency, but will reduce efficiency, because there is a lock upgrade process, this time will need to-xx:-usebiasedlocking to disable the biased lock. Here are the comparison of these types of locks: Lock Advantages Disadvantages Applicable scenarios Biased lock Locking and unlocking does not require additional consumption, and the execution of a non-synchronous method is less

without first checking. A typical example of the Set method is the Unlock () method in the lock class. A thread holding a lock is always able to unlock successfully without checking that the lock is in an unlocked state.The program flow of the set method is usually as follows: Set internal state Notifies the waiting thread Here is an example of

Original article: Http://www.infoq.com/cn/news/2011/08/jprofiler7 J-Technologies Co., Ltd. released jprofiler 7.0 some time ago. Jprofiler is a Java SE/EE profiling tool that features CPU analysis, memory analysis, thread analysis, and Vm telemetry. New Features of version 7.0 include: Analyze the built-in probes for JDBC, JMS, JNDI, Servlet, files, sockets, and processes. You can use the API to customi

("Fromrealsubject");}}publicclass proxysubjectextendssubject{privaterealsubjectrealsubject; The //proxy role internally references the real role @Override public voidrequest () {prerequest (); // Actions that are attached before a real-world role Operation if (Null==realsubject) { realsubject=newrealsUbject ();} Realsubject.request (); //true character completion postrequest (); //actions attached after a real-world role Operation } privatevoidprerequest () {system.out.println (" Prerequest

Real time includes CPU times and waiting, switching, and so on, so it is generally larger than the CPU. Comparisons can determine if the time-consuming operation is within the CPU execution segment. C. The% of the above four indicators indicates the percentage of the function in total time. Easy to see the time ratio of a function. D. calls+recurcalls/total represents the number of external calls + recursion count/total number of times. You can see if the number of calls matches your expectat

the listThere are at least three ways to traverse after JDK1.5: ForEach, iterator, for loop.Package Bupt.xiaoye.charpter2.list;import Java.util.arraylist;import Java.util.iterator;import java.util.List; public class Testfor {public static void Testforeach (List list) {Object Temp;for (object t:list) temp = t;} public static void Testfor (List list) {Object temp;for (int i = 0; i The result of the operation is:As you can see, the direct for loop is the most efficient, followed by iterators and f

Java profiling toolJProfilerIt can be integrated with a variety of IDES and application servers. This article mainly introduces jprofiler andIntelliJ IDEA Integration. 1. Choose Session> IDE integrations from the main menu of JProfiler. It is worth noting that IntelliJ IDEA needs to be disabled when the plug-in is installed. If you run the installation program through the JProfiler Installation wizard, you

Commercial:ANTS Memory Profiler:http://www.red-gate.com/products/dotnet-development/ants-memory-profiler/ANTS Performance Profiler:http://www.red-gate.com/products/dotnet-development/ants-performance-profiler/NET Memory profiler:http://memprofiler.com/JetBrains dottrace:http://www.jetbrains.com/profiler/download/index.htmlSciTech Memory profiler:http://www.scitech.se/Free:CLR profiler:http://msdn.microsoft.com/en-us/magazine/ee309515.aspxSOS Debugging Extension:http://msdn.microsoft.com/en-us/li

middleware and stand-alone version Java thread stack information (for example, under Unix: Kill-3 Full thread dump Java HotSpot (TM) 64-bit Server VM (20.0-b11 mixed mode): # Java EE Middleware, third-party, and custom threads in application software This part is the core of the entire thread stack and is the part that usually takes the most time to parse. The

single instance class client Although the single design pattern is the simplest design pattern shown in the figure below, it presents a number of flaws for unwary Java developers. This article discusses the single case patterns and reveals those flaws. Note: You can download the source code for this article from resources. Single case Mode In design pattern, the author describes a singleton pattern by making sure that a class has only one in

Java reflection is an important feature of the Java language. It briefly analyzes the definition, principles, usage, performance, and application scenarios of reflection. (1) Definition When a program is running, the program structure or variable type can be modified. This language is called Dynamic Language. Java is not a dynamic language, but provides RTTI (Run

Gen, which can be shorter on pause times. Use-XX:+USEPARALLELOLDGC to enable parallel compacting Collector in the JVM startup parameters. Concurrent mark-sweep (CMS) Collector: The concurrency flag clears the garbage collector, for young Gen uses the same garbage collection strategy as parallel Collector, for tenured Gen, Garbage-collected garbage-flagged threads are at the same time as the application thread, while garbage removal requires suspending the application thread, but the pause