Weekly Report 2022.01

Happy New Year 2022

Reading

Feynman Technique

With few days concentration, I finished this book before the coming new year. Well, read is trivial, the hardest part is taking this technique into real life. To be honest, I was over-optimistic about myself.

The main ideas are as below:

Figure out why you’d like to learn a subject, without sufficient reason, it’s not necessary or prepared-enough to put your hand on it. (Maybe a waste of time)
Gain a general understanding about what this subject actually is. Best practice is always learning things from up to bottom. (From the very abstract concept to detailed explanation)
Teach someone with your own words(understanding). After reading a chapter or one video, it will be very helpful if you explain to yourself right away.
While teaching is hard to complete, well, it’s always acceptable to go back and learn again.
Make your own conclusions.

Make sure that your goal must be specific, measurable, achievable, rewarding and time-bound.

Learning

Control Group

CGroup 限制每个进程 (task_struct inside kernel) 的资源 (通过将进程加入到 cgroup 组), cgroup 的结构如下:

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struct cgroup {
    unsigned long flags; // current state of cgroup
    atomic_t count; // reference counter, the count of active tasks
    struct list_head sibling;
    struct list_head children;
    struct cgroup *parent;
    struct dentry *dentry; // cgroup fs entry
    struct cgroup_subsys_state *subsys[CGROUP_SUBSYS_COUNT]; // sub systems (cpu, mem, etc.)
    struct cgroupfs_root *root; //
    struct cgroup *top_cgroup;
    struct list_head css_sets;
    struct list_head release_list;
}

CNM (Container Network Model)

The network mechanism inside project libnetwork.

Network: A linux bridge
Sandbox: A Linux network namespace which contains a container’s configuration (network adapter interface, ip routers)
Endpoint: A linux veth pair

Open Source License

Copy Left: 我赠与你源代码，你回馈相关的修改

Mozilla Public License, version 2 (MPLv2)
GNU Lesser General Public License (LGPL)
GNU General Public License, version 2 (GPLv2)
GNU General Public License, version 3 (GPLv3)
GNU Affero General Public License (AGPL)

Source Available: 允许获取和阅读源代码，但限制使用

Business Source License (BSL)
Elastic License 2.0 (ELv2)

Permissive: 基本无限制

MIT License
BSD License
Apache License, version 2.0 (APL 2.0)

Life

Thought

思考答案的过程，比答案本身更重要 (某种层面上)
经验保证你的下限，好奇心决定你的上限

Anti-mimetic

The social rewards that come from imitating others feel good, but they come at a high price.

From myself

The less you care, the less you scare.
A wise man ought always to follow the paths beaten by great men, and to imitate those who have been supreme, so that if his ability does not equal theirs, at least it will savour of it.
時を超えでも変わらないものこそが本当の宝物。

Other

Unable to determine falsehood
Unknown unknown
Intuition or Cognition
Internalization
Relevance and Context
Where does think fail
First principal thinking
Remix and Permutation VS Authentication and Originality