> it took 2 weeks and 260GB of uncompressed disk space
Is most of that data because of there being like a zillion different views and sortings of the same posts? That’s been the main difficulty for me when wanting to crawl some sites. There’s like an infinite number of permutations of URLs with different parameters because every page has a bunch of different link with auto-generated URL parameters for various things, that results in often retrieving the same data over and over and over again throughout an attempted crawl. And sometimes URL parameters are needed and sometimes not so it’s not like you can just strip all URL parameters either.
So then you start adding things to your crawler like, starting with shortest URLs first, and then maybe you make it so whenever you pick the next URL to visit it will take one that is most different from what you’ve seen so far. And after that you start adding super specific rules for different paths of a specific site.
The slowdown wasn't due to a lot of permutations, but mostly because a) wget just takes a considerable amount of time to process large HTML files with lots of links, and b) MyBB has a "threaded mode", where each post of a thread geht's a dedicated page with links to all other posts of that thread. The largest thread had around 16k posts, so that's 16k² URLs to parse.
In terms of possible permutations, MyBB is pretty tame thankfully. Only the forums are sortable, posts only have the regular and the aforementioned threaded mode to view them. Even the calender widget only goes from 1901-2030, otherwise wget might have crawled forever.
I originally considered excluding threaded mode using wget's `--reject-regex` and then just adding an nginx rule later to redirect any incoming such links to the normal view mode. Basically just saying "fuck it, you only get this version". That might be worth a try for your case
Is most of that data because of there being like a zillion different views and sortings of the same posts? That’s been the main difficulty for me when wanting to crawl some sites. There’s like an infinite number of permutations of URLs with different parameters because every page has a bunch of different link with auto-generated URL parameters for various things, that results in often retrieving the same data over and over and over again throughout an attempted crawl. And sometimes URL parameters are needed and sometimes not so it’s not like you can just strip all URL parameters either.
So then you start adding things to your crawler like, starting with shortest URLs first, and then maybe you make it so whenever you pick the next URL to visit it will take one that is most different from what you’ve seen so far. And after that you start adding super specific rules for different paths of a specific site.