Today's Question:  What does your personal desk look like?        GIVE A SHOUT

SEARCH KEYWORD -- Server monitor



  Why is single threaded Redis so fast

Redis is a high-performance, in-memory key-value database. According to official test reports, it can support around 100,000 QPS (queries per second) on a single machine. However, Redis uses a single-threaded architecture in its design. Why does Redis still have such high performance with a single-threaded design? Wouldn't it be better to use multiple threads for concurrent request processing? In this article, let's explore why Redis has a single-threaded architecture and still maintains its spe...

   REDIS,SINGLE-THREADED,MULTI-THREADING     2023-02-28 05:16:22

  Using Fabric to deploy web app

Many people may use FTP and rsync to synchronize codes to server, this way is fine but it may be troublesome when you need to deploy many times a day, actually there is a simple way if you can spend time on finding the fast way. We introduce Fabric today for deploying web app to remote server. Fabric is a deployment tool written with Python, the biggest feature if it is you no need to login to remote server, you can execute remote commands locally. Here is s simple deployment script written with...

   Fabric, Web deployment,SSH,Python     2012-12-08 03:16:00

  8 very useful and free web security testing tools

With more pervasive of web applications, web security threats are becoming increasingly prominent. Hackers gain web server control by exploiting web server vulnerabilities and SQL injection vulnerabilities, then they may tamper with web content, or steal important internal data, the more serious is to inject malicious code into web pages to affect visitors of websites. Attention is gradually warming up to Web Application Security. Here we recommend eight very useful and free web security testing...

   Website, security,Web security,Attack     2012-07-22 10:59:09

  Data as code

What is a good command line parser API? A good command line parser should consider below 5 aspects: Support convenient help information generation Support sub commands, for example, git has push,pull,commit sub commands. Support single character option, word option, flag option and option with parameter. Support default option, for example, if no -port is set, set it as 5037 Support usage model, for example, tar's -c and -x is mutually exclusive, they belong to different usage models. Here are...

   Command line,API     2013-08-08 22:40:36

  WireGuard VPN: Setup WG_VPN client App on Android phone and connect to local WG_VPN server on VM

We will show the detail steps about how to setup the WireGuard VPN client on an Android phone/pad and configure the VPN client to connect a WG_VPN server in local network. The setup process contents three main steps: Install WireGuard and create a key-pair in WireGuard client. Add the Android client peer information in the WireGuard server’s config file. Config the Android WireGuard client to connect to the server. The test environment network configuration:  Step 1. Install Wire...

   WIREGUARD,VPN,TUTORIAL     2020-10-24 08:46:42

  Redis Cluster and Common Partition Techniques in Distributed Cache

In this post, I will discuss a few common partition techniques in distributed cache. Especially, I will elaborate on my understanding on the use of Redis Cluster. Please understand that at the time of writing, the latest version of Redis is 4.0.10. Many articles on the same topic have a different idea from this post. This is mainly because, those articles are probably outdated. In particular, they may refer to the Redis Cluster implementation in Redis 3. Redis Cluster has been improved...

   REDIS,DISTRIBUTED CACHE,CLOUD COMPUTING     2019-01-17 08:10:37

  Meta tag in HTML header

In server response, we can use response.setHeader() to set the meta information in header of a HTML page. The usage is response.setHeader(name,context); meta is used to simulate the response header of HTTP protocol in HTML page. It should be put between the <head> and </head> tag. 1. <meta name="Generator" content="" > <!--This is to specify the tool which generates this page such as Microsoft FrontPage 4.0 etc --> 2. <meta name="keywords" content=""> <!-- To tel...

   HTTP,meta,HTML,head     2013-05-22 11:34:08

  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

  Mount DD image on Linux

Yesterday, my Raspberry Pi running Arch Linux was not able to boot with error: Kernel Panic, not syncing: no init found. I spent a night on it, but could not find a working solution. The last option is easy: reinstall the system. That is really the last resort, for I do not want to re-setup everything I have done: samba server, Time Machine server, Xunlei Offline Downloader… Unable to mount the SD card The system does not boot, so I need to find a way to get into the file system to identi...

   LINUX,DD IMAGE     2014-06-24 07:49:14

  Sending message to Slack Incoming Webhook using PHP

Slack is a popular work collaboration tool and it provides many features which help teams collaborate. It has one function which allows sending messages to channels from external source such as your own web service -- Incoming Webhook. This is extremely useful when want to monitor something and get notified when some event occurs and it doesn't require complicated setup. To send messages using Incoming Webhook, a service URL has to be generated on Slack and then the message can be posted to this...

   PHP,CURL,SLACK,INCOMING WEBHOOK     2017-03-11 21:32:28