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import imaplib, email, email.parser, email.policy
import html2text
import pprint, sys

#
# Utilities for Debug
#
pp = pprint.PrettyPrinter(indent=4, width=80)

def myprint(str):

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# 生成 dhparam.pem 文件, 在命令行执行任一方法:

# 方法1: 很慢
openssl dhparam -out /etc/nginx/ssl/dhparam.pem 2048

# 方法2: 较快
# 与方法1无明显区别. 2048位也足够用, 4096更强
openssl dhparam -dsaparam -out /etc/nginx/ssl/dhparam.pem 4096

xtao

In this article, I will share some of my experience on installing NVIDIA driver and CUDA on Linux OS. Here I mainly use Ubuntu as example. Comments for CentOS/Fedora are also provided as much as I can.

Table of Contents

• Install NVIDIA Graphics Driver via apt-get
• Install NVIDIA Graphics Driver via runfile
  • Remove Previous Installations (Important)
  • Download the Driver
  • Install Dependencies
  • Creat Blacklist for Nouveau Driver

• Stop lightdm/gdm/kdm

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""" Consistent load-balancing.

We have a few servers and we want a load-balancer to
distribute incoming requests across them in a deterministic
and consistent way - without keeping any counter to make the
decision.

Removing a backend server should not impact users on other
servers.

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#!/bin/bash
 
 
__debug()
{
    if [[ -n ${BASH_COMP_DEBUG_FILE} ]]; then
        echo "$*" >> "${BASH_COMP_DEBUG_FILE}"
    fi
}
 

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Direct links to free Springer maths books (pdf versions)

duplicates = multiple editions

A Classical Introduction to Modern Number Theory,Kenneth IrelandMichael Rosen

A Classical Introduction to Modern Number Theory,Kenneth IrelandMichael Rosen

A Course in Arithmetic,Jean-Pierre Serre

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package main

import (
	"log"
	"bufio"
	"time"
	"os"
	"fmt"
	"io"
	"net"

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Latency Comparison Numbers
--------------------------
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
Send 1K bytes over 1 Gbps network        10,000   ns    0.01 ms
Read 4K randomly from SSD*              150,000   ns    0.15 ms

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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