block-trace

Figure out if your node process is blocked because the CPU is spinning and exit the program with a stack trace if that is the case.

Useful for debugging unresponsive servers.

npm install -g block-trace

Usage

Giving the following example program

console.log('Waiting 1s ...')

setTimeout(function () {
  console.log('Spinning the CPU now!')
  while (1) {}
}, 1000)

If you run this with block-trace by doing the following

block-trace node example.js

After 1s the program will exit with the following output

Waiting 1s ...
Spinning the CPU now!
Error: CPU is blocked
    at /Users/maf/dev/node_modules/block-trace/example.js:5:10
    at Timer.listOnTimeout (timers.js:92:15)

License

MIT