JasonCC JasonCC

shadowsocks作者说的很对的一句话与感想

个人感想:

中国人很投机, 包括本人在部分情况下也是投机者. 总想不劳而获, 抄袭他人劳动成果. 想想我们学生时代的抄袭作弊之风盛行便可知... (然而为什么会这样)
"土皇帝"情节, 因自己在某方面上比别人强, 听听粉丝的追捧, 就觉得自己不可一世, 比别人优越, 殊不知人外有人山外有山, 而且自己在其他方面也有不如他人的地方. (然而为什么会这样)
家长情节总想要一个"家长"来管理一切, 把应该由自己解决的问题抛给别人"包办解决", 图一时之便. 久而久之结果就是并不了解你一切的"家长""包办解决"你的一切, 而你却失去了基本的思考解决问题能力, 看不到目标, 找不到方法, 只好任由"家长"摆布. 这种"爱"是现实的囚笼. (然而为什么会这样)

原文内容:

Tracing QEMU-KVM Interactions

But default in linux you can figure out how many times and for what reasons there is a VM Exit from a VM into the kvm kernel module. However given the ubiquity of vhost and the ability of kvm to emulate most device models directly in the kernel, most of those VM exits do not result in a transition from host kernel into the QEMU. The transitions from VM -> kvm -> QEMU are typically the most expensive.

Here we try to figure out how many of the VM Exits result in the invocation of QEMU.

Tracking VM-KVM Interactions

This can be done very simply with perf

Default

Powerlevel9k

Memory Optimization (Christer Ericson, GDC 2003)
http://realtimecollisiondetection.net/pubs/GDC03_Ericson_Memory_Optimization.ppt

Cache coherency primer (Fabian Giesen)
https://fgiesen.wordpress.com/2014/07/07/cache-coherency/

Code Clinic 2015: How to Write Code the Compiler Can Actually Optimize (Mike Acton)
http://gdcvault.com/play/1021866/Code-Clinic-2015-How-to

This script sets up your Git environment by creating/setting several common aliases and shortcuts for them.

Git cheat list

name of the current banch and nothing else (for automation)
```
git rev-parse --abbrev-ref HEAD
```
all commits that your branch have that are not yet in master
```
git log master..<HERE_COMES_YOUR_BRANCH_NAME>
```

	#!/bin/sh

	# requirements
	# - wget

	# prepare directory
	mkdir -p ~/.local/bin
	mkdir -p ~/.config

	if ! [ -x "$(command -v tmux)" ]; then

	#!/usr/bin/env bash

	set -Eeuo pipefail
	trap cleanup SIGINT SIGTERM ERR EXIT

	script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &>/dev/null && pwd -P)

	usage() {
	cat <<EOF
	Usage: $(basename "${BASH_SOURCE[0]}") [-h] [-v] [-f] -p param_value arg1 [arg2...]

	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

	# --------
	# Hardware
	# --------

	# Opcode - operational code
	# Assebly mnemonic - abbreviation for an operation

	# Instruction Code Format (IA-32)
	# - Optional instruction prefix
	# - Operational code