February 1, 2025
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3 min read
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The /proc
in Linux is a kind of Pseudo file system (also known as Virtual File System), what it saves is a series of special files that store the current running state of the kernel, and the user can check the hardware info and the runnning processes via the files, even adjust some files to change the state of running kernel. The files in /proc
will be refresh in RAM, so the files’ size is 0 bytes.
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January 30, 2025
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1 min read
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I frequently use ifconfig
and cat /proc/net/dev
to examine network information. However, today, my cloud server crashed unexpectedly. I reached out to the cloud support for assistance. The engineer utilized iftop
to analyze the situation. After the issue was resolved, I started to consider using this tool. Now, let’s take a closer look at this powerful utility.
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January 23, 2025
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12 min read
· Page View:
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In python, due to the GIL (Global Interpreter Lock), which is a mutex and ensures only one thread can execute at a time, so the multiple threads parallel execution is not supported under the CPython interpreter. But what about the multiple processes? What is the difference between them? How to choose the right method? Do you know the coroutine? Let’s explore it together.
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January 22, 2025
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2 min read
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The test methods in Go mainly include three types: unit test, benchmark test, and example test.
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January 20, 2025
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21 min read
· Page View:
![](https://cdn.jsdelivr.net/gh/timerring/scratchpad2023/2024/2025-01-21-11-49-28.png)
Do you really understand the video technology? What is the frame rate
, resolution
, bit rate
and their relationships? Do you know the parameters p
and K
in the terminology 1080p
and 4K
? Do you know how to describe the video quality? What is the Blu-ray Disc
on earth? What the difference between the codec such as H.264/AVC
, H.265/HEVC
, AV1
? You may notice the Apple ProRes
in apple, so do you really understand what it for? Do you know the HDR
and Dolby Vision
? So why there are so many tailers such as .mp4
, .mkv
, .flv
, etc?
Now this Video Technology 101 will introduce them to you.
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January 19, 2025
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12 min read
· Page View:
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Message queues are a form of asynchronous service-to-service communication. They are important in enhancing a system’s scalability, reliability, and maintainability.
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January 19, 2025
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7 min read
· Page View:
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Do you know the basic method to manage the traffic? There are four methods: Load Balancers, Reverse Proxies, Forward Proxies, and API Gateways. And they have different features and usage scenarios.
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January 19, 2025
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14 min read
· Page View:
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In the daily life, we often hear about different kind of API, such as REST API, GraphQL API, WebSocket, Webhook, RPC and gRPC even the SOAP, so do you know the difference between them? How to choose the right API for your project?
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January 19, 2025
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0 min read
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Do you really know the encode and decode in Python?
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January 18, 2025
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2 min read
· Page View:
![](https://cdn.jsdelivr.net/gh/timerring/scratchpad2023/2024/2025-01-18-22-43-49.png)
It has been a long time that the linux use init
to manage the startup process, such as sudo /etc/init.d/apache2 start
or service apache2 start
, but the init
is serial. To address this issue, the systemd
was born. The d is the abbreviation of daemon
, which means the systemd
is a daemon manager. The systemd substitutes the initd and becomes the default main process PID 1
.
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