max-rocket-internet

CPU: percentage of limit

A lot of people land when trying to find out how to calculate CPU usage metric correctly in prometheus, myself included! So I'll post what I eventually ended up using as I think it's still a little difficult trying to tie together all the snippets of info here and elsewhere.

This is specific to k8s and containers that have CPU limits set.

To show CPU usage as a percentage of the limit given to the container, this is the Prometheus query we used to create nice graphs in Grafana:

sum(rate(container_cpu_usage_seconds_total{name!~".*prometheus.*", image!="", container_name!="POD"}[5m])) by (pod_name, container_name) /

Windsooon

海外兔

anvk

--- PSQL queries which also duplicated from https://github.com/anvk/AwesomePSQLList/blob/master/README.md
--- some of them taken from https://www.slideshare.net/alexeylesovsky/deep-dive-into-postgresql-statistics-54594192

-- I'm not an expert in PSQL. Just a developer who is trying to accumulate useful stat queries which could potentially explain problems in your Postgres DB.

------------
-- Basics --
------------

-- Get indexes of tables

PurpleBooth

Project Title

One Paragraph of project description goes here

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes. See deployment for notes on how to deploy the project on a live system.

Prerequisites

igrigorik

Navigation and Resource Timing provides timing data for the fetch, but currently there is no interoperable way for the server to communicate own timing information to the client. For example:

• What steps were taken to generate the resource, and how long each took. Many sites already embed this type of information via HTML comments - e.g. wordpress emits <!--Page generated in X.X seconds.--> , and many sites provide more detailed stats (cache, db, generation) to enable performance debugging.
• If proxied, where was the time spent - e.g. time to fetch from origin, time to process response, etc.

Instead of relying on arbitrary HTML comments, we can define an HTTP header that can be used to send key-value pairs in a well defined format. Making this data available via a well defined interface would...

• Allow UA and other developer tools to automatically annotate appropriate timelines.
• Allow analytics vendors to gather this data for operational analysis.
• Allows proxies and CDNs to append custom timing d

staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

---

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

---

xdite

專案名稱： Rails新手村網站

主旨：收集 Rails 有用 Link

基本功能

• 使用者可以登入 / 登出
• 使用者可以使用 Facebook 登入 https://github.com/xdite/auto-facebook

qrtt1

由於 Google API 久久才會用一次，但它的文件對我來說實在是不好閱讀，應該花點時間把它筆記起來才是。

學習曲線分析

閱讀 Google API 使用文件，覺得難以閱讀的主要原因是它分成許多部分，每一部分不一定跟你要做的功能相關，而是在滿足你能使用 API 的基本條件。要攻略使用文件就必需清楚知道哪些是屬於「共通科目」、「必修科目」屬於任何產品的 API 使用前都必需滿足的。

內容分為下列主題：

1. API 的設計哲學：Service Discovery (描述 API 的 API)
2. API 開通與證認：API Console & OAuth 2

hellerbarde

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD