HACKER Q&A
📣 FreeHugs

Why does Node.js start so slow?


time php -r 'echo 123;'

outputs:

    123
    real 0m0.031s
    user 0m0.023s
    sys 0m0.008s
time python3 -c 'print (123)'

outputs:

    123
    
    real 0m0.022s
    user 0m0.019s
    sys 0m0.004s
time node -e 'console.log(123);'

outputs:

    123

    real 0m0.578s
    user 0m0.551s
    sys 0m0.028s
Why is the node version more than 10 times slower than the PHP and Python versions?

  👤 efortis Accepted Answer ✓
What's your output for: `which node` and `node -v`

On my M1 Pro:

    python3 -c 'print (123)'    0.02s user 0.01s system 86% cpu 0.036 total
    node -e 'console.log(123)'  0.04s user 0.01s system 88% cpu 0.053 total
👤 raxxorraxor
I guess the reason is that the runtime of node is so much larger than that of Python and PHP. I think the Node runtime is already at > 50MB as a binary.

I don't know how large Python and PHP runtimes are, but I know python is often stripped down to a few kilobytes for embedded systems.

I guess if you preload the runtimes before executing these commands, the execution should be fairly similar for each one (near zero, more depending on I/O).