同时运行的进程数是有限制的。

[Tzdy]

可以通过ulimit -u查看最大运行数。

nodejs在用child_process调用其他二进制文件时（eg.. git, wc），会受到最大进程的影响，如果达到最大进程数，就会报错.

Error: read ENOTCONN
    at tryReadStart (node:net:614:20)
    at Socket._read (node:net:625:5)
    at Socket.Readable.read (node:internal/streams/readable:487:10)
    at Socket.read (node:net:666:39)
    at new Socket (node:net:415:12)
    at Object.Socket (node:net:286:41)
    at createSocket (node:internal/child_process:328:14)
    at ChildProcess.spawn (node:internal/child_process:445:23)
    at spawn (node:child_process:700:9)
    at /Users/mac/Documents/web/server/gogs/ty-git/dist/git.js:59:46
Emitted 'error' event on Socket instance at:
    at emitErrorNT (node:internal/streams/destroy:157:8)
    at emitErrorCloseNT (node:internal/streams/destroy:122:3)
    at processTicksAndRejections (node:internal/process/task_queues:83:21) {
  errno: -57,
  code: 'ENOTCONN',
  syscall: 'read'
}