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A comment on Kirc – A tiny IRC client written in POSIX C99. Parent comment

Re:Kirc – A tiny IRC client written in POSIX C99 by moonchild on Wednesday September 16, 2020 @06:03PM (#24498524)
> on Linux, only 48 of 64 bits are available for VM

That is on amd64, not linux. And arm does the same thing. (It's also 256tb, not 250tb.)

Newer intel cpus use 5-level paging[1], which gives you 128pb VM.

1. https://en.wikipedia.org/wiki/Intel_5-level_paging

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Re:Kirc – A tiny IRC client written in POSIX C99 by fulafel on Thursday September 17, 2020 @12:22AM (#24501162)
Also it's 48-bit just on current amd64 chips, it's not an architectural amd64 property - your binary is compatible with >48bit VA space of the future (unless you yourself misguidedly bake the 48-bit assumption into it). But I guess the point was to point out lower bounds.
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Re:Kirc – A tiny IRC client written in POSIX C99 by moonchild on Thursday September 17, 2020 @03:01AM (#24501912)
Right; hence the mention of intel 5-level paging with 56-bit virtual address space.
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