I've searched all around the web for this, but can't find desirable answer.
There's many resources(even here, on SE) that tell wordpress isn't capable of handling large, massive web portals(but probably can, with some custom modifications). However there's some big brands out there who does use wordpress, just to name a few: chicago.suntimes.com and techcrunch.com
My question is what actually one need to do in order to big, massive news websites(like the above) would functional without performance issues.
Note: I hope it won't sound to you as too broad, and I hope there's someone who have the knowledge and experience to answer this question. Thanks.
It definitely is a broad question. But it's also one that's not limited to WordPress.
There have been many similar questions in the past though, one example is WordPress for a very large website.
Simply put, you need a scalable setup and good caching (object cache, static file cache, etc.). You want to serve as many users as possible without directly hitting the bottleneck that is your application (in this case WordPress).
The exact setup really depends on your needs, number of users and their location, your budget, and other factors.