SEARCH KEYWORD -- TECH BLOG



  A mini guide to HTTP referer

In HTTP header, there is a field named Referer which is to provide the referrer of the current accessed page. In this post, we will introduce the usage of HTTP referer field. On the web, when a user visits a webpage, s/he must be from some place. This place is usually referred a s referer. This information is very important to some website operators and server owners as they want to know where they get the traffic from and this helps them provide better service for potential targeted users. In t...

   HTML,HTTP REFERER,REFERRERPOLICY     2019-06-29 02:23:25

  China has blocked Wikipedia again

Recently lots of Chinese found they experienced problems while trying to access Wikipedia, the world's largest and most well-known free encyclopedia. It turns out that the notorious Chinese GFW(Great Firewall) is playing the critical role here. It blocks the Chinese version of Wikipedia. The reason why the Chinese version of Wikipedia is blocked is said to be that Wikipedia has changed its default protocol from HTTP to HTTPS. This change made it difficult for the GFW to filter some sensiti...

   CHINA,WIKIPEDIA,GFW,BLOCKED,NEWS     2015-12-05 19:04:12

  Build Hadoop environment in Linux

Hadoop standalone installation: 1. Install JDK Install JDK with below command: sudo apt-get install sun-java6-jdk Configure Java environment, open /etc/profile, add below contents: export JAVA_HOME = (Java installation directory) export CLASSPATH =".:$JAVA_HOME/lib:$CLASSPATH" export PATH = "$JAVA_HOME/:PATH" Verify installation of Java Type java --version, if it outputs Java version information, then Java is successfully installed. 2. Install SSH Install SSH with below command: sudo ...

   Hadoop.Linux,Configuration     2013-07-31 23:22:27

  Why TCP needs 3 handshakes

Prerequisite Knowledge First, let's look at the control bits and state machine of TCP, which form the basis for understanding the three-way handshake of TCP. TCP Packet Control Bits The control bits in the TCP packet header are used to control the status of the TCP connection and can indicate various control information such as connection establishment, termination, reset, etc. There are six common control bits: SYN (Synchronize Sequence Numbers): Requests to establish a connection (part of the...

   REASON,NETWORK,TCP,EXPLANATION,HANDSHAKE     2024-09-28 08:57:52

  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

  noConflict mechanism in jQuery

Many JavaScript frameworks like to use $ as function or variable name, jQuery is one of them. In jQuery, $ is just a reference to window.jQuery, so even if $ is deleted, window.jQuery will still be available to ensure the whole library can work normally. jQuery API design takes fully consideration of multiple frameworks conflicts, we can use jQuery.noConflict function to easily handle control. jQuery.noConflict accepts one optional boolean parameter[1] to determine whether to hand jQuery object ...

   jQuery,noConflict,$     2013-03-14 19:40:36

  What does a Bing driven Siri mean to Google?

On Tuesday, Apple announced that Bing would become the default search engine of the upcoming iOS 7. This is another Google service kicked out by Apple after Youtube and Google Maps.For Siri: if the default system of Siri can not answer your question, it will try to search the Internet. Currently, Siri connects to the Safari browser by default, and Safari's primary search engine is Google (Can change to Yahoo or Bing). But in iOS 7, Siri's default search engine will be replaced by Bing. Siri will...

   Siri,Bing,Google     2013-06-12 00:20:34

  How to monitor user behavior in webpage

Sometimes there is a need for website owners to monitor user behavior on the site so that they can know what pages are mostly visited and which parts are more popular so that they can provide better service to their users. These behavior usually contain user clicks, user mouse over events etc. These data can be sent back to server when triggered with some meta data. In this post, we will cover a few ways to monitor user behavior on a web portal and send data back to backend sever. 1. Synchronous...

   HTML,BEACON API,PING,USER BEHAVIOR     2019-06-29 06:06:59

  Concurrency vs Parallelism

Concurrency and parallelism are two related concepts which deal with executing tasks "simultaneously". From Sun's Multithreaded Programming Guide: Concurrency: A condition that exists when at least two threads are making progress. A more generalized form of parallelism that can include time-slicing as a form of virtual parallelism. Parallelism: A condition that arises when at least two threads are executing simultaneously. These two definitions are too formal to be understood easily. On t...

   Concurrency,Parallelism,Thread     2013-08-07 23:42:33

  Text editor vs IDE

A meaningless editor war Many people like to debate which editor is the best. The biggest controversy is between Emacs and vi. vi supporters like to say: "Look it's very fast to type in vi, our fingers no need to leave the keyboard, we even no need to use the up,down,left and right keys" Emacs supporters often downplayed this and said: "What's the use of typing fast if I just need to press one key and it equals to dozens keys you type in vi?"In fact, there is another group of people who like to ...

   Editor,IDE,Structured editor,vi     2013-05-20 12:03:39