write large text to file using nodejs

writeLargeFile.js

//writes a billion numbers to file. size: 9.3GB
let writeStream = fs.createWriteStream("./output");
writeStream.on('open',async ()=>{
while (k<=10**9){
  let written = k%10 == 0 ? writeStream.write(k.toString()+"\n") : writeStream.write(k.toString()+" ");
  /**
  imp stuff..., without which out-of-memory error is thrown.
  [https://stackoverflow.com/a/40221132/7314900] stream.write() method returns false when stream has large enough data. so,
  */
  if(!written){
    //https://stackoverflow.com/a/50360972/7314900 - update-II
    await new Promise(resolve =>  writeStream.once('drain',resolve));
  }
  k++;
}
writeStream.end();
);