cookie parse: add fast path

[gurgunday]

Important change is at line 70, if we don't have any = left in the string, no need to continue the loop as we do not have any key-value pairs left

[mcollina]

Lgtm

How much more throughput this gives us?

[gurgunday]

File: benchmark/cookie.js

Test case exaggerated here to make the point, but idea is that can just finish parsing if no = is left

New:

npx autocannon -H "Cookie":";;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;" http://127.0.0.1:5001
Running 10s test @ http://127.0.0.1:5001
10 connections


┌─────────┬──────┬──────┬───────┬──────┬─────────┬─────────┬───────┐
│ Stat    │ 2.5% │ 50%  │ 97.5% │ 99%  │ Avg     │ Stdev   │ Max   │
├─────────┼──────┼──────┼───────┼──────┼─────────┼─────────┼───────┤
│ Latency │ 0 ms │ 0 ms │ 0 ms  │ 0 ms │ 0.01 ms │ 0.05 ms │ 13 ms │
└─────────┴──────┴──────┴───────┴──────┴─────────┴─────────┴───────┘
┌───────────┬─────────┬─────────┬─────────┬────────┬───────────┬──────────┬─────────┐
│ Stat      │ 1%      │ 2.5%    │ 50%     │ 97.5%  │ Avg       │ Stdev    │ Min     │
├───────────┼─────────┼─────────┼─────────┼────────┼───────────┼──────────┼─────────┤
│ Req/Sec   │ 68,479  │ 68,479  │ 77,183  │ 78,143 │ 76,360.73 │ 2,607.46 │ 68,444  │
├───────────┼─────────┼─────────┼─────────┼────────┼───────────┼──────────┼─────────┤
│ Bytes/Sec │ 14.9 MB │ 14.9 MB │ 16.7 MB │ 17 MB  │ 16.6 MB   │ 565 kB   │ 14.9 MB │
└───────────┴─────────┴─────────┴─────────┴────────┴───────────┴──────────┴─────────┘

Req/Bytes counts sampled once per second.
# of samples: 11

840k requests in 11.01s, 182 MB read

Old:

npx autocannon -H "Cookie":";;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;" http://127.0.0.1:5001
Running 10s test @ http://127.0.0.1:5001
10 connections


┌─────────┬──────┬──────┬───────┬──────┬─────────┬─────────┬───────┐
│ Stat    │ 2.5% │ 50%  │ 97.5% │ 99%  │ Avg     │ Stdev   │ Max   │
├─────────┼──────┼──────┼───────┼──────┼─────────┼─────────┼───────┤
│ Latency │ 0 ms │ 0 ms │ 0 ms  │ 0 ms │ 0.01 ms │ 0.05 ms │ 12 ms │
└─────────┴──────┴──────┴───────┴──────┴─────────┴─────────┴───────┘
┌───────────┬─────────┬─────────┬─────────┬─────────┬─────────┬──────────┬─────────┐
│ Stat      │ 1%      │ 2.5%    │ 50%     │ 97.5%   │ Avg     │ Stdev    │ Min     │
├───────────┼─────────┼─────────┼─────────┼─────────┼─────────┼──────────┼─────────┤
│ Req/Sec   │ 65,215  │ 65,215  │ 70,207  │ 70,847  │ 69,648  │ 1,511.98 │ 65,193  │
├───────────┼─────────┼─────────┼─────────┼─────────┼─────────┼──────────┼─────────┤
│ Bytes/Sec │ 14.1 MB │ 14.1 MB │ 15.2 MB │ 15.4 MB │ 15.1 MB │ 329 kB   │ 14.1 MB │
└───────────┴─────────┴─────────┴─────────┴─────────┴─────────┴──────────┴─────────┘

Req/Bytes counts sampled once per second.
# of samples: 11

766k requests in 11.01s, 166 MB read

[mcollina]

LGTM