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

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”

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

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

A place for everything, and everything in its place.

A cold in the head in June is an immoral thing.

I've always tried to go a step past wherever people expected me to end up.

To admit regret is to understand that we are fallible - that there are powers beyond us. To admit regret is to lose control not only of a difficult past but of the very story we tell about our present. To admit sincere and abiding regret is one of our greatest but unspoken contemporary sins.

If the political will is there, we can solve anything.

Women and minorities have excelled beautifully in comedy, but very few women are the lead in a drama.

Chance leads to discoveries, and mutagenesis is a way to enhance one's chances of finding a surprise. Often it is the exceptional observations that lead to advances; once you understand exceptions, you understand the whole picture.

No-one can replace Richard Wright - he was my musical partner and my friend.

You know, you get to a certain age, 45, 50, I don't know when it happens, I said, 'Jesus, all I got is a certain amount of time. Maybe I should think about using it a little better.'

I thought of myself as kind of an anarchist all my whole adult life, from the days when I was 15 or 16.

The death of a 20-year-old woman is intuitively worse than that of a 2-month-old girl, even though the baby has had less life. The 20-year-old has a much more developed personality than the infant, and has drawn upon the investment of others to begin as-yet-unfulfilled projects.

What happens a lot in film, though not so much in the theatre, is that you get stroked and sort of massaged, like a little guinea pig.

I think I hid my singing talent from a lot of my friends at school because I didn't want to alienate anyone. If everyone was singing along in the car to a Madonna song, I didn't join in because when we're younger we're afraid of sticking out or showing off, when in fact we should own those things that make us really unique.

Bass players are always the intellectual kind but nobody knows it.

With any story I write, I could actually write it from three or four different perspectives, which would end with a completely different moral at the end.

When its time to go off to work, or work out, I have a great support system: a great nanny and friends who offer to help out whenever they can.

If someone explains me the definition of love, I will give my life to the person. Love is a thing which is difficult to understand. Love is always evolving.

I started out as a 16 year old registering people to vote.

My friends that are snobs think its cool I did a movie with Albert Brooks.

If you don't fix latent failures in your system, you're asking for trouble.

I took one look at you. That's all I meant to do and my heart stood still.

I just always loved stand-up. It's like magic. You say something, and a whole room full of people laughs together. Say something else, they laugh again. The fact that people come to see that and participate in that... I don't know, it's just like magic.

There are things that can only be said with a good string of cussing. I'm definitely fond of a few choice words. They say things that nothing else can say. Gotta love it.

If we want an international trade deal that advances the interests of our own people, then perhaps we don't need a 'fast-track' but a regular track: where the president sends us any proposal he deems worthy, and we review it on its own merits.