组件是可复用的 Vue 实例，所以它们与 new Vue 接收相同的选项，例如 data、computed、watch、methods 以及生命周期钩子等。仅有的例外是像 el 这样根实例特有的选项

缓存技术蕴含的是空间换时间的思想；压缩体现的是时间换空间的思想；分布式思想也最初体现在 CPU 的设计和实现上

普通磁盘的寻道时间是 10ms 左右，而相比于磁盘寻道花费的时间，CPU 执行指令和内存寻址的时间都在是 ns（纳秒）级别，从千兆网卡上读取数据的时间是在μs（微秒）级别

某些层次负责的是对下层不同实现的抽象，从而对上层屏蔽实现细节。比方说 VFS 对上层（系统调用层）来说提供了统一的调用接口，同时对下层中不同的文件系统规约了实现模型，当新增一种文件系统实现的时候，只需要按照这种模型来设计，就可以无缝插入到 Linux 文件系统中

分层架构可以让我们更容易做横向扩展。如果系统没有分层，当流量增加时我们需要针对整体系统来做扩展。但是，如果我们按照上面提到的三层架构将系统分层后，那么我们就可以针对具体的问题来做细致的扩展

分层架构需要考虑的另一个因素，是层次之间一定是相邻层互相依赖，数据的流转也只能在相邻的两层之间流转

Happens-Before 并不是说前面一个操作发生在后续操作的前面，它真正要表达的是：前面一个操作的结果对后续操作是可见的

导致可见性的原因是缓存，导致有序性的原因是编译优化，那解决可见性、有序性最直接的办法就是禁用缓存和编译优化

Java 内存模型在 1.5 版本对 volatile 语义进行了增强。怎么增强的呢？答案是一项 Happens-Before 规则

Java 内存模型规范了 JVM 如何提供按需禁用缓存和编译优化的方法

final 修饰变量时，初衷是告诉编译器：这个变量生而不变，可以可劲儿优化

“同一时刻只有一个线程执行”这个条件非常重要，我们称之为互斥。如果我们能够保证对共享变量的修改是互斥的，那么，无论是单核 CPU 还是多核 CPU，就都能保证原子性了。

一个或者多个操作在 CPU 执行的过程中不被中断的特性，称为“原子性”

使用 watch 选项允许我们执行异步操作 (访问一个 API)，限制我们执行该操作的频率，并在我们得到最终结果前，设置中间状态。这些都是计算属性无法做到的

如果 <navigation-link> 没有包含一个 <slot> 元素，则该组件起始标签和结束标签之间的任何内容都会被抛弃。

计算属性是基于它们的响应式依赖进行缓存的。只在相关响应式依赖发生改变时它们才会重新求值。这就意味着只要 message 还没有发生改变，多次访问 reversedMessage 计算属性会立即返回之前的计算结果，而不必再次执行函数

I don't think there is a single social issue I haven't spoken on.

Fitness has always been one of the top priorities in my life because that's the way I grew up, with soccer being the sport of choice.

I'd love for there to be a situation - a world in which that's just not even a question anymore. We are all filmmakers - different stripes, genders, sexual orientations, colors - and our work can be taken on its own terms. I'm really looking forward to that day.

At what point in time can our government fire someone whose gross negligence left four Americans dead in Benghazi?

That DMC Act is a disgrace. And the problem with independent art in this country is that independent artists have been economically blacklisted.

The U.S. is by far the biggest exporter of arms in the world. It was true during the Clinton administration, and it's true during the Bush administration. It's bipartisan.

Madness ends sometimes. The Gods decree it, not man.

There is no doubt that America is a superpower of the world and we cannot ignore them.

We need an amendment that gives us the right to vote protected by the federal government and the Constitution.

I was a good student, I was good at soccer, I was vice president of the student council, I was a pretty girl.

Anyone can deal with victory. Only the mighty can bear defeat.

There's only two choices when life goes wrong. You deal with it, or you check out, and, like 90% of people, I go for the former.

At 16, I was more resilient and easygoing than I am now.

The usual false conclusions of mankind are these a thing exists therefore it has a right to exist.

The unemployment rate is still twice as high for blacks as for whites.

When I'm off the road, and I can really control my diet down to the calorie, I juice seven days a week. Every afternoon, whatever I have at hand, beets, carrots, ginger, whatever. I juice, literally, every single day. And on the road, I try to find fresh juice wherever I can.

I don't do anything unless I can give it 100%.

I feel SF is going through an experimental phase right now.

I think politics today is all about false choices: You can have a robust energy economy and a challenged environment, or a great environment and no economy. That's a false choice. You can do both.

It's a nice neighborhood, like the one I left. My home borough is Brooklyn and Queens.

Have fun. Do something nobody else had done before, or has done since.

No one is asking for an Oprah in Chief. Anyhow, Obama is too chilly by nature ever to be convincing as a human care package.

We know were getting old when the only thing we want for our birthday is not to be reminded of it.

I would go to sketch groups and draw. I really enjoyed the subject matter, but I wasn't good at it.