SEARCH KEYWORD -- DISTRIBUTED CACHE



  What is Hystrix and How does Hystrix work

Background In distributed systems, there is one effect where the unavailability of one service or some services will lead to the service unavailability of the whole system, this is called service avalanche effect. A common way to prevent service avalanche is do manual service fallback, in fact Hystrix also provides another option beside this. Definition of Service Avalanche Effect Service avalanche effect is a kind of effect where the service provider fails to provide service which causes t...

   AVALANCHE EFFECT,HYSTRIX,DISTRIBUTED SYSTEM     2019-02-04 06:00:38

  System programming is still there

System programming is the practice of writing system software. System software lives at a low level, interfacing directly with the kernel and core system libraries. Your shell and your text editor, your compiler and your debugger, your core utilities and system daemons are all system software. But so are the network server, the web server, and the database. These components are entirely system software, primarily if not exclusively interfacing with the kernel and the C library. But nowadays more...

   System programming     2014-02-27 05:46:48

  What will the value of Integer.valueOf(127) == Integer.valueOf(127) be in Java?

Do you really understand how Java does the integer comparison? OK, ignore the statements in the post title. What we are interested in is another set of comparison statements. Let's first see below code snippet. public class IntegerComparison { public static void main(String[] args) { Integer a = 127, b = 127; Integer c = 128, d = 128; System.out.println(a == b); System.out.println(c == d); } } What do you think the output will be? Are they both displaying true? You will find out t...

   JAVA,==,EQUALSTO     2018-01-13 22:18:15

  Special ARP Uses: Gratuitous ARP, ARP Probe, and ARP Announce

In an Ethernet environment, all data is ultimately sent in the form of a Layer 2 Ethernet Frame, which includes the Src MAC, Dst MAC, and other headers such as CRC, etc. Ethernet will then deliver the data to the destination. When we program, we often specify the IP and Port, but rarely specify the MAC address. So, how is the Frame sent out? This is done by the operating system. If the system does not know the MAC address corresponding to an IP, it will send a broadcast ARP request (since this r...

   ARP,NETWORK,LINUX     2024-11-07 20:57:26

  Will PHP __autoload() function really affect performance?

IntroductionRegarding to PHP performance, the most frequently discussed is the __autoload() function. Many people say that this function will affect the performance very much, some other people say that opcode will affect __autoload() as well. So we will have some tests on these two.EnvironmentPHP 5.3.9 -- Launch under fastcgi modeNginx 1.1.12eAccelerator 0.9.6.1ScreenshotsLaunch pageeAccelerator(In php.ini) configurationFile structure(each Test file has over 6000 lines of code)Testing With e...

   PHP,__autoload(),opcode,performance     2012-05-09 11:25:26

  Load and execute JavaScript

When we load and execute JavaScript in a webpage, there are many points we need to care about because of its design and feature. There are two features about JavaScript execution in a browser: 1). The JavaScript codes will be executed immediately once loaded;2). When JavaScript codes are being executed, they will block the following contents (including page rendering and other resources downloading). So if there are multiple js files to be loaded, these codes will be executed sequentially. Since...

   JavaScript,async,defer,load,execute     2013-06-07 04:53:46

  The First Bite on etcd Code

Etcd, one of the crucial components of Kubernetes. If APIServer is the heart, then etcd is the blood vessel that sends the end state of Kubernetes resources to various “organs”, providing high-speed, stable storage, and supporting APIServer’s high load performance. What if the etcd is not working properly? Just the condition as someone has a vascular disease. The deeper you know about them, the better diagnose you can make when issues occur. from unspl...

   SOURCE CODE,ETCD     2022-02-12 01:03:14

  Testing LLM on MacOS with Llama

As a programmer, I always believe that the best way to understand something is by actually getting the hands dirty by testing it out ourselves. In past few years, with the introduction of ChatGPT, AI and associated technologies such as LLM come to a hot spot in tech industry and there are lots of platforms available and different models coming out for people to test out. This post I will demonstrate a step-by-step guide on how to run Llama(a Meta LLM) on a MacOS machine with a model. This will j...

   GUIDE,LLAMA,LOCAL,HUGGING FACE,QWEN     2024-11-17 13:36:28

  Hadoop or Spark: Which One is Better?

What is Hadoop? Hadoop is one of the widely used Apache-based frameworks for big data analysis. It allows distributed processing of large data set over the computer clusters. Its scalable feature leverages the power of one to thousands of system for computing and storage purpose. A complete Hadoop framework comprised of various modules such as: Hadoop Yet Another Resource Negotiator (YARN MapReduce (Distributed processing engine) Hadoop Distributed File System (HDFS) Hadoop Common Thes...

   COMPARISON,HADOOP,SPARK     2018-11-22 07:08:57

  How does MySQL handle DROP TABLE

A few days ago, when executing DROP TABLE in MySQL, all processes including DDL and DML were hung until DROP TABLE was completed. I am confused about this phenomenon. I have reviewed the source codes of MySQL to check how MySQL internally handle DROP TABLE. When user trigger DROP TABLE command: ########################MySQL SERVER drop table######################## /* Sql_table.cc  delete (drop) tables. */bool mysql_rm_table( )   /*   Execute the drop of a normal or temporary...

   MySQL,DROP TABLE     2012-09-24 11:34:05