When writing programs for user mode (ring 3 on x86), you hardly need to care (except sometimes use some segment override prefixes (cf. https://news.ycombinator.com/item?id=13052076), which pedantically is "dealing with the MMU", since because of the MMU this works; but in my opinion it is not necessary to understand the technical details behind it, why this works).
On the other hand, if you are an OS ("operating system", here I don't mean "open source") developer, you probably better know the details of the MMU.
Concerning https://news.ycombinator.com/item?id=13052892: I also consider the author's statement as misleading that one has to know how segmentation works. The knowledge of about segmentation is absolutely necessary for x86-16 (real mode), which many people tend to associate with assembly (because there seem to be many more assembly tutorials available for DOS/x86-16 than for x86-32 or even x86-64), but hardly relevent for people who just write user mode code.
When writing programs for user mode (ring 3 on x86), you hardly need to care (except sometimes use some segment override prefixes (cf. https://news.ycombinator.com/item?id=13052076), which pedantically is "dealing with the MMU", since because of the MMU this works; but in my opinion it is not necessary to understand the technical details behind it, why this works).
On the other hand, if you are an OS ("operating system", here I don't mean "open source") developer, you probably better know the details of the MMU.
Concerning https://news.ycombinator.com/item?id=13052892: I also consider the author's statement as misleading that one has to know how segmentation works. The knowledge of about segmentation is absolutely necessary for x86-16 (real mode), which many people tend to associate with assembly (because there seem to be many more assembly tutorials available for DOS/x86-16 than for x86-32 or even x86-64), but hardly relevent for people who just write user mode code.