老外提问: Hi, I have an sql query which takes 8 seconds in the first run. The next run there after takes 0.5 seconds and all consecutive runs take 0.5 seconds. Is the plan getting cached? How do i make this query run in 0.5 second in the first run itself
Spring speeds up development by keeping your application running in the background Rails程序自动增加:spring和spring-watcher-listen. 增加一个spring-commands-rspec gem $ spring status 检测是否启动spring Spring is running: 7424 spring server | gatherer | started 220 h
list.ensureCapacity竟然会变慢 jdk1.8 应该是做了优化了: public class Test10 { public static void main(String[] args) { ArrayList<Integer> list = new ArrayList<>(); long beginTime = System.currentTimeMillis(); for (int i = 0; i < Integer.MAX_VALUE / 300;
前言 最近在翻<高性能JavaScript>这本书(2010年版 丁琛译),感觉可能是因为浏览器引擎的改进或是其他原因,书中有些原本能提高性能的代码在最新的浏览器中已经失效.但是有些章节的有些内容还是相当不错的,譬如第八章编程实践,为了方便以后的查阅,对此做个总结.失效的代码也会在以后做更进一步的探索. 避免双重求值 这个优化策略很好理解,我们可能都已经不知不觉地运用在了实际的编程中: // not use this setTimeout('alert("hello world&qu
