--cpu-prof

启动时开始 V8 CPU 分析器，并且在退出前将 CPU 分析文件写入磁盘。

¥Starts the V8 CPU profiler on start up, and writes the CPU profile to disk before exit.

如果未指定 --cpu-prof-dir，则生成的分析文件放在当前工作目录中。

¥If --cpu-prof-dir is not specified, the generated profile is placed in the current working directory.

如果未指定 --cpu-prof-name，则生成的分析文件名为 CPU.${yyyymmdd}.${hhmmss}.${pid}.${tid}.${seq}.cpuprofile。

¥If --cpu-prof-name is not specified, the generated profile is named CPU.${yyyymmdd}.${hhmmss}.${pid}.${tid}.${seq}.cpuprofile.

$ node --cpu-prof index.js
$ ls *.cpuprofile
CPU.20190409.202950.15293.0.0.cpuprofile 拷贝

如果指定了 --cpu-prof-name，则提供的值将用作文件名的模板。以下占位符受支持，并将在运行时替换：

¥If --cpu-prof-name is specified, the provided value is used as a template for the file name. The following placeholder is supported and will be substituted at runtime:

• ${pid} — 当前进程 ID

  ¥${pid} — the current process ID

$ node --cpu-prof --cpu-prof-name 'CPU.${pid}.cpuprofile' index.js
$ ls *.cpuprofile
CPU.15293.cpuprofile 拷贝