Minix Book question

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username291
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Minix Book question

Post by username291 »

Virtual Memory, Section 4.3, Page 389

"...In Fig. 4-10(b) we see how the two-level page table works in this example.
On the left we have the top-level page table, with 1024 entries, corresponding to
the 10-bit PT1 field. When a virtual address is presented to the MMU, it first
extracts the PT1 field and uses this value as an index into the top-level page table.
Each of these 1024 entries represents 4M because the entire 4-gigabyte (i.e., 32-
bit) virtual address space has been chopped into chunks of 1024 bytes."

"...virtual address space has been chopped into chunks of 1024 bytes." - I don't understand this. 1024 bytes? Is it a mistake?
alexfru
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Re: Minix Book question

Post by alexfru »

username291 wrote: Sun Apr 19, 2026 12:37 pm "...virtual address space has been chopped into chunks of 1024 bytes." - I don't understand this. 1024 bytes? Is it a mistake?
The Modern Operating Systems book from 1992 has "chopped into 1024 chunks." at the end of the sentence (note the period).
If your edition says what you say it does, it's a mistake.
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pearmypie
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Re: Minix Book question

Post by pearmypie »

username291 wrote: Sun Apr 19, 2026 12:37 pm ...virtual address space has been chopped into chunks of 1024 bytes.
Are you reading the book based on Minix 1?
Before 2.0, Minix supported Motorolla 68k processors, which used 1024 bytes pages (instead of the familiar 4096 bytes we see today on x86_64). Maybe it's referring to this.
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