mirror of
https://github.com/anticensority/runet-censorship-bypass.git
synced 2024-11-28 04:13:43 +03:00
29 lines
1.5 KiB
Markdown
Executable File
29 lines
1.5 KiB
Markdown
Executable File
## PAC-Script Performance Analysis
|
||
|
||
__Warning:__ this experimentation wasn't implemented in the extension yet.
|
||
|
||
Somewhere in PAC-script you may want:
|
||
|
||
```javascript
|
||
if (Is_subdomain_of( host, blocked_hosts ))
|
||
return 'use proxy';
|
||
```
|
||
|
||
You have to make `Is_subdomain_of` very fast.
|
||
This check is executed on each request. You should watch memeory consumption too.
|
||
|
||
The naive solution is to keep array of blocked ips and check if the host resolves to one of the ips.
|
||
You may do it with `indexOf`, binary search, etc.
|
||
The shortcoming of every ip solution is that __some providers resolve blocked hosts to wrong ips__, so we eventually need list of hosts.
|
||
|
||
I have tested different [solutions](https://github.com/ilyaigpetrov/anti-censorship-russia/tree/master/pac-generator/src), and depicted [results](./benchmark/Output.txt) in the following chart:
|
||
|
||
![Host Lookup Chart: Time-Memory, Hits-Misses](./chart/host-lookup-chart.png)
|
||
|
||
* __IPs indexOf__ – Blocked IP is searched by `indexOf`
|
||
* __IPs binary__ – Blocked IP is searched by binary search. For some reason miss time slightly increased.
|
||
* __IPs switch__ – Simply `switch(Blocked_IP) { case1: ... caseN: return true }`. Works even better than binary search. Magic.
|
||
* __Hosts switch__ – Radix trie built on `switch`. Comparable to __IPs switch__.
|
||
* __Hosts reversed binary__ – binary search on hosts, but hosts are kept in reversed form: _"gro.evichra"_ instead of _"archive.org"_. It shouldn't really affect anything, but it does, maybe because I also use `dnsDomainIs` instead of `===`.
|
||
|