1. LINUX System : Lecture 6 Bong-Soo Sohn
Lecture notes acknowledgement : The design of UNIX Operating System

2. Architecture of the UNIX
libraries
system call interface
file subsystem
process
control
subsystem
inter-process
communication
scheduler
memory
management
hardware control
hardware
buffer cache
device drivers
character
block
user Level
kernel Level
hardware Level
trap
user programs
좌측에 파일서브시스템과 우측에 프로세스 서브시스템이 가장 핵심되는 축이 된다.
3종류의 레벨로 나뉘어져 있다 – user level, kernel level, hardware level

3. Libraries (1) process control libraries system call interface
user programs
libraries
trap
user Level
kernel Level
system call interface
file subsystem
process
control
subsystem
inter-process
communication
scheduler
memory
management
buffer cache
device drivers
character
block
hardware control
kernel Level
hardware Level
hardware

4. File Subsystem (1) process control libraries system call interface
user programs
libraries
trap
user Level
kernel Level
system call interface
file subsystem
process
control
subsystem
inter-process
communication
scheduler
memory
management
buffer cache
device drivers
character
block
hardware control
kernel Level
hardware Level
hardware

5. File Subsystem (2) Managing files Allocating file space
Administering free space
Controlling access to files
Retrieving data for users
Interact with set of system calls
open, close, read, write, state, chown, chmod …

6. Buffering Mechanism (1)
user programs
libraries
trap
user Level
kernel Level
system call interface
file subsystem
process
control
subsystem
inter-process
communication
scheduler
memory
management
buffer cache
device drivers
character
block
hardware control
kernel Level
hardware Level
hardware

7. Buffering Mechanism (2)
Interact with block I/O device drivers to initiate data transfer to and from kernel.

8. Process Control Subsystem (1)
user programs
libraries
trap
user Level
kernel Level
system call interface
file subsystem
process
control
subsystem
inter-process
communication
scheduler
memory
management
buffer cache
device drivers
character
block
hardware control
kernel Level
hardware Level
hardware

9. Process Control Subsystem (2)
Responsible for process synchronization.
Interprocess communication (IPC)
Memory management
Process scheduling
Interact with set of system calls
fork, exec, exit, wait, brk, signal …
파일시스템과 프로세스 컨트롤 시스템간의 서로 연계되는 때는 프로그램 실행을 위해서 메모리에 프로그램을 로딩할 때이다.

10. Process Control Subsystem (3)
Memory management module
Control the allocation of memory
Scheduler module
Allocate the CPU to processes
Interprocess communication
There are several forms.

11. Hardware Control (1) process control libraries system call interface
user programs
libraries
trap
user Level
kernel Level
system call interface
file subsystem
process
control
subsystem
inter-process
communication
scheduler
memory
management
buffer cache
device drivers
character
block
hardware control
kernel Level
hardware Level
hardware

12. Hardware Control (2)
Responsible for handling interrupts and for communicating with the machine.