@koa/router v11+ benchmarks 10x SLOWER than v10!

[jeremy-daley-kr]

Don't just take my word for it... Run this benchmark: https://github.com/delvedor/router-benchmark

These are the time differences I'm seeing from v10 to v11:

v11

======================
 koa-router benchmark
======================
short static: 472,156 ops/sec
static with same radix: 480,787 ops/sec
dynamic route: 466,452 ops/sec
mixed static dynamic: 474,721 ops/sec
long static: 482,460 ops/sec
wildcard: 480,499 ops/sec
all together: 80,170 ops/sec

v10

======================
 koa-router benchmark
======================
short static: 4,301,032 ops/sec
static with same radix: 4,178,987 ops/sec
dynamic route: 4,033,963 ops/sec
mixed static dynamic: 3,810,142 ops/sec
long static: 3,998,437 ops/sec
wildcard: 4,125,847 ops/sec
all together: 625,066 ops/sec

Even v7-v8 were faster:

v8

======================
 koa-router benchmark
======================
short static: 1,422,593 ops/sec
static with same radix: 1,385,510 ops/sec
dynamic route: 1,344,517 ops/sec
mixed static dynamic: 1,323,915 ops/sec
long static: 1,384,331 ops/sec
wildcard: 1,389,524 ops/sec
all together: 226,891 ops/sec


v7

======================
 koa-router benchmark
======================
short static: 1,498,510 ops/sec
static with same radix: 1,488,757 ops/sec
dynamic route: 1,465,601 ops/sec
mixed static dynamic: 1,419,721 ops/sec
long static: 1,457,910 ops/sec
wildcard: 1,422,492 ops/sec
all together: 237,266 ops/sec

Something happened between v8 and v9 that made things way better... And then v11 dialed it WAY back.

Note: I had to change koa-router's wildcard to a regex.

[jeremy-daley-kr]

Did some more digging from this comparison page: koajs/router@v10.1.1...v11.0.0

Tried each commit, and seemed to pinpoint it to this commit:
koajs/router@d0c6d8b

CC: @titanism

Something in that commit made things VERY slow

[titanism]

This is an amazing find @jeremy-daley-kr (albeit I haven't reproduced yet nor tested benchmarks).

Perhaps in the commit it was the change in for loops, e.g. koajs/router@d0c6d8b#diff-9be572fb49ced6cd74dfd6787ba235abfa40f12b2c5abf47ac93a7a6d6cbc6c0L27-R28?

[jeremy-daley-kr]

@titanism Do you think this should be submitted as a bug to the @koa/router repo? I'd like to get more community support, and make sure sight of this isn't lost.

[jeremy-daley-kr]

I believe I've at least ruled out layer.js. I copied/pasted the previous version of layer.js and router.js, and only saw the numbers shoot back up after reverting router.js.

[jeremy-daley-kr]

Found it!
It's this guy...

const { debuglog } = require('util');
const debug = debuglog('koa-router');

Any particular reason you swapped that in for the previous:

const debug = require('debug')('koa-router');

That single change appears to be the culprit.

[jeremy-daley-kr]

Pull request here:
koajs/router#173

[titanism]

Wow, that's INSANE! Native node debugger vs a third party package 🤦 Is there a GitHub issue about this in the Nodejs repo?

[titanism]

This is now resolved. We have published a new version of v12 and v11 of koa-router and @koa/router (mirrored packages).

See koajs/router#173.

Thank you sincerely @jeremy-daley-kr – we're going to get this into production at Forward Email today (GitHub at @forwardemail).