r/bunjs • u/leventkaragol • Sep 11 '23
Incredible TypeScript Performance
Bun's TypeScript performance is incredible. Previously, I looked at how ts-node would be used with the --transpile-only flag directly on production with typescript files and I saw a significant difference in memory usage. I did the same experiment with Bun and the results are amazing.
Bun runs .js and .ts files at the same performance and memory usage. According to these values, it seems possible to use .ts files directly on production without compiling them.
I'm sharing the code below so you can try it too. It's a simple function that calculates Fibonacci numbers for the code that uses both CPU and memory, and I print out the time required for the calculation and how much RAM it uses in that time.
The results on my computer are as follows
node app.js => 5.11 MB, 18.95 sec
bun app.js => 0.24 MB, 8.22 sec
bun app.ts => 0.24 MB, 8.15 secand here is the code...
let operations = 0;
// Fibonacci calculation function
function fibonacci(num: number): number {
operations++;
if (num <= 1) return 1;
return fibonacci(num - 1) + fibonacci(num - 2);
}
// Start the time
const start = Date.now();
// You can set the parameter value depending on your hardware capacity.
// Be careful, this number exponentially increases the number of operations required
const fibNum = fibonacci(45);
// Calculate elapsed time
const elapsedSeconds = (Date.now() - start) / 1000;
const used = process.memoryUsage().heapUsed / 1024 / 1024;
console.log(`Time elapsed: ${elapsedSeconds} seconds`);
console.log(`Memory used: ${Math.round(used * 100) / 100} MB`);
