SEARCH KEYWORD -- Data center


  China has 591 million netizens now

CNNIC(China Internet Network Information Center() released its 32nd research report on Internet usage in China on July 17 Beijing Time. According to the report, China has 591 million netizens until June 2013, among them 464 million are phone Internet users. Chinese netizens surf the Internet 21.7 hours a week. The report shows that China's netizens reached 591 million as of the end of June 2013,  an increase of 26.56 million people compared to the end of 2012. Internet coverage rate is 44...

   CNNICInternet usage     2013-07-18 02:27:52

  4 Technologies That Impact You (Without Your Knowledge)

Our world to day is so driven by technology that it’s easy to stay on top of the major changes and developments. We know when there’s a major new innovation in personal electronics; we know that the 5G network is rolling out this year; we track the progress of smart cars, learning thermostats, and interactive home speakers. We even tend to care about how major tech companies around the world are performing! However, as “plugged in” as we all seem to be to the world of tec...

   AI,DATA ANALYTICS,IOT     2020-04-16 06:35:54

  How does PHP session work?

This article is about how PHP session works internally. Below are the steps : 1. Session in PHP is loaded into PHP core as an extension, we can understand it as an extension. When session extension is loaded, PHP will call core functions to get the session save_handler, i.e interface or functions for reading and writing session data. By default, PHP will handle session data by writing and reading files on the server. But PHP also supplies custom methods for handling session data, we can use sess...

   PHP, session, mechanism     2012-12-28 13:36:49

  Click and Drag on xkcd

xkcd is a webcomic created by Randall Munroe. The comic's tagline describes it as "a webcomic of romance, sarcasm, math, and language." Also some webcomics about IT may frequently appear on it. For example, the following one-- People who know Unix will understand it easily. In fact, xkcd is a Geek culture, many comics inside this site can only understood by some specified group of people. The comic began in September 2005 when Munroe decided to scan doodles from hi...

   xkcd, 1110,Click and Drag     2012-11-05 11:23:19

  Why cannot compare double values directly for equality?

A question in PHP: Get some value from the database and use floatval() to convert it to floatint point value, then compare it with another value which is also converted to floating point value with floatval(). These two values are the same when using var_dump() to output, the two outputs are float(8.87), they are the same. But when comparing them for equality, the result is weird., they are not equal. Why?To analyze this question, we need to start with PHP data types. PHP uses weak types. In PHP...

   PHP,floating, precision,compare,equality     2012-06-27 09:01:36

  How Kafka achieves high throughput low latency

Kafka is a message streaming system with high throughput and low latency. It is widely adopted in lots of big companies. A well configured Kafka cluster can achieve super high throughput with millions of concurrent writes. How Kafka can achieve this? This post will try to explain some technologies used by Kafka. Page cache + Disk sequential write Every time when Kafka receives a record, it will write it to disk file eventually. But if it writes to disk every time it receives a record, it would ...

   BIG DATA,KAFKA     2019-03-08 09:42:57

  CSS position explained

CSS has two very important properties on determining the position of an element in webpage: display and position. display is used to determine how elements are grouped and displayed on the page. While position is used to determine the exact position of an element on a page. And this post would explain position property in detail. position is used to determine the exact position of an element on a page. It has five possible values. static relative absolute fixed sticky sticky is supported start...

   CSS,STICKY,CSS3     2019-11-22 19:57:52

  Short SASS tutorial

If you learned CSS before, you should know that CSS is not a programming language. You can use it to design webpage style, but you cannot use it for programming, i.e, CSS is what designer uses, not what programmer uses. Programmer may think that CSS is very troublesome, it has no variables, no conditional statements, it just allows line-by-line description of HTML elementsLuckily, CSS preprocessor appear which makes CSS programmable. The general idea of CSS preprocessor is using a programming la...

   CSS,SASS,programmable,variable,condition,comment     2012-06-22 08:38:18

  Today in history : Steve Wozniak invented Apple I in 1975

The original Apple Computer, also known retroactively as the Apple I, or Apple-1, is a personal computer invented by Steve Wozniak ion 29th June, 1975. Wozniak's friend Steve Jobs had the idea of selling the computer. Features:CPU : MCStek 6502CPU Speed : 1MHzBus Speed : 1MHzMemory : 8KbResolution : 60.05 Hz, 40*24 charactersPower : 58WPrice : $666.66The Apple I went on sale in July 1976 at a price of US$666.66, because Wozniak "liked repeating digits" and because they originally sold it to a lo...

   Apple I,History,Steve Wozniak     2012-06-29 06:00:08

  Symbian is dead

Although Nokia has repeatedly indicated that it will give up Symbian, but no one thought their actions would be so fast. This morning, some people from Nokia Italy said Symbian's life will be ended prematurely. The source revealed some information of Symbian's future.  The Nokia 808 will be equipped with the Symbian Belle FP1 system, Nokia will soon provide updates to this hand phone with Symbian Belle FP2, the platform will no longer receive any updates there after..Of course, this also me...

   Nokia,Symbian,Death     2012-05-24 04:57:16

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