java - Why does exist WeakHashMap, but absent WeakSet?

Set<Object> weakHashSet = Collections.newSetFromMap( new WeakHashMap<Object, Boolean>()); As seen in Collections.newSetFromMap documentation, passing a WeakHashMap to get a Set.... Read More

java - Young , Tenured and Perm generation

The Java garbage collector is referred to as a Generational Garbage Collector. Objects in an application live for varying lengths of time depending on where they are created and how they are used. Th... Read More

r - What is the difference between gc() and rm()

First, it is important to note that the two are very different in that gc does not delete any variables that you are still using- it only frees up the memory for ones that you no longer have access t... Read More

memory management - Is there garbage collection in PHP?

Yes there is, [here]'s a nice article describing its pitfalls. In PHP > 5.3.0, there is also the gc_enable function.... Read More

java - Can the JVM GC move objects in the middle of a reference comparison, causing a comparison to fail even when both sides refer to the same object?

Java Bytecode instructions are always atomic in relation to the GC (i.e. no cycle can happen while a single instruction is being executed). The only time the GC will run is between two Bytecode inst... Read More

How does Java Garbage Collection work with Circular References?

Java's GC considers objects "garbage" if they aren't reachable through a chain starting at a garbage collection root, so these objects will be collected. Even though objects may point to each other t... Read More

google chrome - How to force JavaScript to deep copy a string?

JavaScript's implementation of ECMAScript can vary from browser to browser, however for Chrome, many string operations (substr, slice, regex, etc.) simply retain references to the original string rat... Read More

Java 7 (JDK 7) garbage collection and documentation on G1

The G1 garbage collector is not the default in my installation of Java, version 1.7.0_01. You can see for yourself by using with some extra command line options: > java -XX:+PrintCommandLineFlags -XX... Read More

What is the garbage collector in Java?

The garbage collector is a program which runs on the Java Virtual Machine which gets rid of objects which are not being used by a Java application anymore. It is a form of automatic memory management... Read More