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  8 most successful open source products

Open source itself is a successful product. It is not only liked by many personals, many famous enterprises like itAlthough there are numerous open source projects and open source products, which is the most successful among them? "Success" is defined as the widely used + well known here. In many successful open source products, only a minority leaders. Here we share 8 most successful open source products we think they deserve to be.LinuxReason: Linux + GNU = GNU / Linux. It has been almost 2...

   Open source,MySQL,Linux,BIND,BSD     2012-04-19 08:29:00

  One reason why mcrypt responds slowly

This morning one colleague came over and talked about one script which used mcrypt responded very slowly, the server configurations are fine. But the reason for the slowness is unknown. Here is one script which reproduces the issue: <?php $dmcryptText = "dummy"; $key = "foobar"; $size = mcrypt_get_iv_size(MCRYPT_BLOWFISH,MCRYPT_MODE_ECB); $iv = mcrypt_create_iv($size); //Take care $m = mcrypt_ecb(MCRYPT_BLOWFISH, $key, $dmcryptText, MCRYPT_DECRYPT, $iv); var_dump($m); When 20 requests of&...

   SOLUTION,SLOW,MCRYPT,RESPONSE,PHP     2012-09-27 12:03:16

  Integer overflow

You may be familiar with integer overflow, but what you may not be familiar with is how gcc handles signed integer overflow. First let's look at the standard, for unsigned integer, the standard says : A computation involving unsigned operands can never overflow, because a result that cannot be represented by the resulting unsigned integer type is reduced modulo the number that is one greater than the largest value that can be represented by the resulting type. In other words, unsigned integer ov...

   Integer overflow,gcc,Linux     2012-10-20 13:33:10

  When will resizing be triggered in Java HashMap?

HashMap is one of the most frequently used collection types in Java, it stores key-value pairs. Ideally it expects to use hash table which expects the data access time complexity to be O(1), however, due to hash conflicts, in reality, it uses linked list or red-black tree to store data which makes the worst case time complexity to be O(logn).  Although collections are using data structures like arrays and linked lists, unlike arrays, they will dynamically resize when there is not enough spa...

   JAVA,RESIZE,HASHMAP,THRESHOLD     2020-05-02 20:41:19

  An alternative way to parse URL in JavaScript

Normally when we need to process URL in JavaScript, we may use the location object. Then we can use location.hostname,location.href,location.port etc to get the information we need. In this post, we will parse an URL with an alternative way. We can use an URL to create a DOM object by calling document.createElement("a"). The complete code is: function parseURL(url) { var a = document.createElement('a'); a.href = url; return { source: url, protocol: a.protocol.replace(':',''), host: a.ho...

   URL,location,parse     2014-03-03 07:05:11

  Memory related exception analysis in Java

Java Virtual Machine Specification divides the memory of JVM into several areas : Heap, Stack, The Program Counter register and Method area etc. In HotSpot JVM, heap is composed of Young, Tenured and Perm. There are different OutOfMemory error can happen in different memory area. Next is an overview of some of these OOM errors. StackOverflowError The JVM will allow only a specified number of stacks created nested. An JVM option -Xss can be set to determine the maximum stack size. If the num...

   Java, Memory model, Memory exception, OOM     2015-01-19 06:54:27

  What is the Right Length of a Blog Article?

The length of your blog posts can build your website or break it. If you thought that this is a myth then you are wrong. Pleasing the search engines is one of the targets of SEO efforts. However, you have to please your visitors as well. With good traffic then you will get good ranking on the Search Engine Results pages (SERPs). One of the best ways to increase your traffic is to make sure that once a visitor lands on your site then they will come again for more information. The length of your b...

   DIGITAL MARKETER ,SEO,SEO TOOLS     2016-03-05 04:18:28

  One thought about JavaScript exception handle

Due to network, browser and cache issues, the JS executed in production may produce different results from the testing environments. Sometimes they may produce exceptions. Front-end developers may encounter this kind of exceptions frequently. But how to log and use them is seldomly considered by them. Actually, exception handling includes two steps : log and use. 1. Log Regarding to log error, this is relatively convenient, since in each browser, there is one interface called window.onerror. win...

   JaavScript,Log,Exception,Email     2013-03-18 12:50:21

  Different ways of handling concurrent job in GoLang

GoLang provides very good support of concurrency and the way to make some code to run concurrent is pretty simple and straightforward. Adding a simple go before a normal function call will make the function call asynchronous. In real cases normally people would concurrently run some jobs to improve the speed and efficiency. One important part of running jobs concurrently is about aggregating results so that the consequent function call would be able to proceed. There are multiple ways handling t...

   COMPARISON,WORKER POOL,WAITGROUP,CONCURRENT     2021-05-15 11:13:53

  etcd installation and usage

etcd is an open source and highly available distributed key-value storage system and is commonly used in critical data storage and service discovery and registration use cases. It is focusing on: Simple: well-defined, user-facing API (gRPC) Secure: automatic TLS with optional client cert authentication Fast: benchmarked 10,000 writes/sec Reliable: properly distributed using Raft etcd and Redis both support key-value storage and can be set up in distributed systems. Also Redis supporst more key...

   ETCD,TUTORIAL,RAFT,DISTRIBUTED SYSTEM     2021-03-07 03:10:33

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