Grant privileges Syntax GRANT <OPERATION> ON <TABLE> TO <USER> [<USER1> <USER2> ...] [WITH GRANT OPTION]; <USER> 可为 PUBLIC，意为所有人。注意：使用 PUBLIC 授予权限，意味着未来创建...

Permissions: PTE_R allows page to be read. PTE_W allows page to be written. PTE_U allows page to be accessed by user. PTE_V left clear in unused PTEs, which seems to be VALID flag. Thing...

C -> Asm / processors Every processor has an associated instruction set architecture (ISA) C -> Asm (.S) -> .o files -> executables RISC-V & x86-64 x86-64 3 full books ...

Terms PRIME render offload PRIME render offload is the ability to have an X screen rendered by one GPU, but choose certain applications within that X screen to be rendered on a different GPU. DR...

Address spaces An address space is the range of memory addresses that a process can reference. Memory management unit Between CPU and memory, there is memory management unit (MMU), which transla...

Some registers that may help work out the error in riscv: scause (Supervisor Cause Register) indicates the type of the page fault. sepc: Supervisor Exception Program Counter stval (Superviso...

Isolation Real world examples Think in Strawman design: If no operating system, there is no strong isolation between programs. Unix interface abstracts the hardware resources. processes: ...

This lab requires python<=3.12 (to import module pipes). I’d like to record my process of implementing primes.c. At first, I didn’t know that subprocess who forked from the parent should clos...

OS purposes Abstract the hardware Both for convenient and portability Multiplex Of applications Isolation Between applications Sha...

What is multicast Imagine this scenario: An example of network topology for multicast Now A wants to send same packets to address group containing B, C, E, and X. It can simply send packets ove...