melin

Docker Hub 镜像加速器

国内从 Docker Hub 拉取镜像有时会遇到困难，此时可以配置镜像加速器。

Dockerized 实践 https://github.com/y0ngb1n/dockerized

Docker daemon 配置代理

参考 Docker daemon 配置代理

melin

1. kubernetes 安装：https://me.jinchuang.org/archives/441.html
2. kubernete 认证：https://www.sharpcode.cn/devops/kubernetes-authn-authz/
3. kubernetes ConfigMap 和 Secrets：https://www.qikqiak.com/post/understand-kubernetes-configmap-and-secrets/
4. Secret 的使用：https://www.qikqiak.com/post/use-secret-in-k8s/
5. Kubernetes RBAC 详解：https://www.qikqiak.com/post/use-rbac-in-k8s/
6. Kubernetes Operator 快速入门教程：https://www.qikqiak.com/post/k8s-operator-101/
7. kubernetes 持久化存储(一): https://www.qikqiak.com/post/kubernetes-persistent-volume1/
8. CentOS 7 下 yum 安装和配置 NFS(k8s NFS环境搭建)：https://qizhanming.com/blog/2018/08/08/how-to-install-nfs-on-centos-7
9. kubernetes包管理工具helm和tiller的安装：https://www.jianshu.com/p/e3483d9439f2

melin

##服务代码

```python
#!/usr/bin/env python2
#coding=utf-8

import tornado.ioloop

import tornado.web
from tornado.escape import json_encode

melin

/* BTrace Script Template */
import com.sun.btrace.annotations.*;
import static com.sun.btrace.BTraceUtils.*;
import java.lang.reflect.Field;

@BTrace
public class TracingScript {

	/*
	 * 获取方参数、返回值信息；获取方法调用时间

melin

public class ArrayQueueSemaphore implements Queue {
	private final Semaphore notFull = new Semaphore(10);
	private final Semaphore notEmpty = new Semaphore(0);
	private final ReentrantLock lock = new ReentrantLock();
	
	private final String[] connections = new String[10];
	int putIndex, takeIndex, count;
	
	public void put(String e) throws InterruptedException {
		notFull.acquire();

melin

package com.github.melin.concurrnt.future;

import java.util.concurrent.CompletableFuture;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import java.util.function.BiFunction;
import java.util.function.Consumer;
import java.util.function.Function;
import java.util.function.Supplier;

melin

1. Send HTTP GET Request

  String url = "http://www.google.com/search?q=httpClient";
 
	HttpClient client = HttpClientBuilder.create().build();
	HttpGet request = new HttpGet(url);
 
	// add request header
	request.addHeader("User-Agent", USER_AGENT);
	HttpResponse response = client.execute(request);

melin

1、ByteBuf支持同时读写操作，包含writerIndex和readerIndex两个变量，如果readerIndex值超过writerIndex，将会抛出IndexOutOfBoundsException错误。
2、ByteBuf支持head buffer（jvm堆中）和direct buffer，堆外分配buffer成本更高。
3、使用ByteBuffer实例：
	ByteBuf heapBuf = ...;
	if (heapBuf.hasArray()) { #1
		byte[] array = heapBuf.array(); #2
		int offset = heapBuf.arrayOffset() + heapBuf.position(); #3
		int length = heapBuf.readableBytes(); #4
		YourImpl.method(array, offset, length); #5
	} 

melin

ChannelInboundHandlerAdapter
	@Override 
	public void channelRead(ChannelHandlerContext ctx, Object msg) { 
		System.out.println(ìServer received: ì + msg); 
		ctx.write(msg) #2 
	} 
	@Override 
	public void channelReadComplete(ChannelHandlerContext ctx) { 
		ctx.writeAndFlush(Unpooled.EMPTY_BUFFER) 
		.addListener(ChannelFutureListener.CLOSE); #3 

melin

import java.io.*;
import java.util.*;
import sun.jvm.hotspot.memory.*;
import sun.jvm.hotspot.oops.*;
import sun.jvm.hotspot.debugger.*;
import sun.jvm.hotspot.runtime.*;
import sun.jvm.hotspot.tools.*;
import sun.jvm.hotspot.utilities.*;

public class DirectMemorySize extends Tool {