bad-container-example

Dockerfile

FROM node

RUN mkdir /demo
COPY io-wasting.js /demo/

CMD ["/usr/local/bin/node", "/demo/io-wasting.js"]

io-wasting.js

// Hacked together example container. Goes off and wastes tons of IO cycles.
var fs = require('fs');

someObscureLibrary();

function someObscureLibrary() {
    var file = '/tmp/io-file-' + Math.random();

    var buffer = 'Hello Node.js: ' + Math.random();

    fs.open(file, 'a+', function (err, fd) {
        if (err) {
            console.error("Failed to write: " + file + " " + err);
            closeDelete(fd, file);
        } else {
            fs.write(fd, buffer, 0, buffer.length, function (err) {
                if (err) {
                    console.error("Failed to write: " + file + " " + err);
                    closeDelete(fd, file);
                } else {
                    fs.fsync(fd, function (err) {
                        if (err) {
                            console.error("Failed to write: " + file + " " + err);
                        }
                        closeDelete(fd, file);
                    })
                }
            })
        }
        someObscureLibrary();

    });
}

function closeDelete(fd, file) {
    fs.close(fd, function () {
        fs.unlink(file, function () {

        })
    })
}