sflow collector

The garbage collector is a special feature that distinguishes Java from other programming languages. It frees programmers from the heavy work of manually reclaiming memory space. In the Java Programmer certification exams of SUN, the garbage collector is mandatory and generally accounts for about 6% of the total score. But because SUN's Java Programming Language SL-275 curriculum standard textbooks, the con

stack. -xx:survivorratio=4: Sets the ratio of the size of Eden and survivor in the younger generation. Set to 4, the ratio of two survivor to one Eden area is 2:4, and a survivor area represents 1/6 of the entire young generation. -xx:maxpermsize=16m: Set the persistent generation size to 16m. -xx:maxtenuringthreshold=0: sets the maximum age for garbage. If set to 0, then the young generation object does not go through the survivor area, directly into the old generation. For older g

GC Algorithm Garbage Collector overviewGarbage collection Garbage Collection is often referred to as the "GC", which was born in the 1960 MIT Lisp language, and has matured for more than half a century.In the JVM, the program counter, virtual machine stack, and local method stack are all born with threads, and stack frames are loaded and out of the stack with the entry and exit of the method, and automatic memory cleanup is realized, so our memory gar

1. PrefaceGarbage collector is the previous chapter of the garbage collection algorithm theoretical knowledge of the specific implementation of the different virtual machines provided by the garbage collector may be a great difference, and we must explain in advance that there is no best garbage collector, more than a universal

efficiency is very high. According to the characteristics of the Cenozoic, there are few objects that still exist, but what to do if a survivor space cannot provide enough space for the surviving object to be stored. The answer is to go to the old age to rent a little memory for emergency In some extreme cases, the target survival rate may be 100%, when more memory needs to be requested from the old age One, serial collector Cenozoic collectors, usi

Master three garbage algorithms, seven garbage collectors, and learn what garbage collection algorithms are used for each garbage collector, as well as knowledge points about SafePoint.garbage Collection Algorithm1. Tag-purge algorithm (mark-sweep)tags (such as the accessibility algorithm) are all objects that need to be recycled, and all tagged objects are reclaimed after the tag is marked.Disadvantage: The labeling and purging process is inefficient

The garbage collector is a specific implementation of memory recycling, the Java virtual machine specification does not specify its implementation, different vendors, different versions of the virtual machine provides a large variety of garbage collectors. This article mainly introduces the garbage collector in the HotSpot virtual machine.Various garbage collectorsShows different garbage collectors, each of

This article is based on Zhou Zhiming's "in-depth understanding of Java virtual machines"If the collection algorithm is the method of memory recycling, the garbage collector is the specific implementation of memory recycling. There is no provision for how the garbage collector should be implemented in the Java Virtual Machine specification, so different vendors, different versions of the virtual machines, m

Read the Java Paper garbage collector type article, here to do a summary, the article part of the translation from the Java Paper GC collector, part of the summary of their own, the image from the network, which is only used to understand the expression.One, JVM GC garbage collector typeThe JVM's garbage collector is b

If the collection algorithm is the method of memory recycling, then the garbage collector is the specific implementation of memory recycling. In the Java Virtual Machine specification, how the object garbage collector should be implemented does not have any rules, so different vendors, different versions of the virtual machines provided by the collector may be qu

Introduction Garbage collection technology is not the Java language Initiative, the 1960 was born at MIT Lisp is the first real use of memory dynamic allocation and garbage collection technology language. Three issues to consider for garbage collection technology are: 1. Which memory needs to be recycled 2. When to recycle 3. How to Recycle The distribution of Java Memory Runtime regions, where program counters, virtual machine stacks, and local method areas are all born with threads, and a

New generation collectors for hotspot virtual machines There are seven main types of hotspot garbage collectors: As shown in the picture:The upper part of the figure is the new generation of garbage collectors, the following section represents the old age of the garbage collector, the two garbage collector between the line means that two collectors with the use. Serial

http://blog.csdn.net/java2000_wl/article/details/8030172 Click on the Open link HotSpot JVM Collector There are 7 collectors, divided into two, the new generation of collectors, the following is the old age collector. If there is a connection between the two collectors, it means they can be used in combination.serial (serial GC) collectorThe serial collector is

, the garbage collector will never reclaim Objectobj = new Object (); The corresponding object such as Obj.equels (NewObject ()) can be obtained directly through the objective lens. And so the Obj object is a strong reference to the subsequent newobject, and only if the obj reference is released, the object will be released, which is also the encoding form we often use. 2, soft reference Must be referenced and reclaimed before memory overflows, and ca

with the thread, and out of the thread, so that the memory allocation and recovery of these areas are deterministic, there is no need to too much consideration of the recycling problem, because the end of the method or the end of the thread, memory naturally with the recycling. The Java heap and method areas are different and different! (How not to say the catchy), this part of the memory allocation and recycling is dynamic, it is the garbage collector