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Comment by qwerty456127 | Hacker News Reader

I just wonder how many consumer applications actually need more than 3 GiBs of RAM per process (and I fear to imagine such an app and the idea these are going to become common). As for now only professional (data science, graphics/multimedia editing, CAD etc) and server-side apps may need that much AFAIK, 64-bit pointers seem a waste on an average PC.

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64 bit pointers are pretty important for security. When using ASLR, a certain number of the bits cannot be randomized. This leaves you with a randomization space of about 12 bits with 32-bit addresses, but over 40 bits of randomization with 64 bit addresses.

Our company bought a nasty piece of proxy/security software that injects a bunch of DLLs right at the center of the address space. 2GB is small if you lose 256MB on this kind of contraption. We had regular problems when ASLR made unfortunate random choices at startup, and not enough continuous adress space was available for end user software.The only option was a reboot.

A browser with several tabs open, some of them being more web applications than pages, can easily reach that limit.

Like it or not, more and more applications are being replaced with web applications, and many of use simply have too many communication channels, and have web apps open for a calendar, slack, email, WhatsApp etc.

Individual browser tabs are often kept as separate processes, though.

3 GiBs of virtual space can get exhausted pretty quick, particularly when working with large files or a lot of mmaps fragmenting the virtual space. Just because a process doesn't need more than 3 GiBs of physical RAM doesn't mean it's happy with only having 3 GiBs of virtual address space.

Video games will probably get there easily.

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