1 Carnegie Mellon A Tour of Computer Systems Instructors: Sejin Park

2 Carnegie Mellon Overview 1.1 Information is Bits + Context 1.2 Program Translation 1.3 Compilation Systems 1.4 Processors - Hardware Organization, Running a Program 1.5 Caches 1.6 Storage Hierarchy 1.7 Operating Systems - Processes, Threads, Virtual memory, Files 1.8 Communication Networks 1.9 Concurrency and Parallelism, Computer System Abstractions

3 hello.c #include int main() { printf(“hello, world\n); return 0; }

4 Carnegie Mellon 1.1 Information is Bits + Context Bit Byte ASCII : represent text characters File : sequence of bytes  Text file  Binary file

5 Carnegie Mellon 1.2 Programs Are Translated

6 Carnegie Mellon 1.3 Compiler Structure

7 Carnegie Mellon 1.3 Compiler Phases

8 Carnegie Mellon Hardware Organization

9 Carnegie Mellon Running a Program

10 Carnegie Mellon Running a Program

11 Carnegie Mellon Running a Program

12 Carnegie Mellon 1.5 Caches

13 Carnegie Mellon 1.6 Storage Hierarchy

14 Carnegie Mellon 1.7 Operating Systems

15 Carnegie Mellon Process Process : Program in Execution

16 Carnegie Mellon Process Execution

17 Carnegie Mellon Process State Transition

18 Carnegie Mellon Process Control Block struct task_struct { pid_t pid; /* process identifier */ long state; /* state of the process */ unsigned int time_slice /* scheduling information */ struct task_struct *parent; /* this process’s parent */ struct list_head children; /* this process’s children */ struct files_struct *files; /* list of open files */ struct mm_struct *mm; /* address space of this process */... } PCB representation in Linux / C

19 Carnegie Mellon Threads

20 Carnegie Mellon Threads

21 Carnegie Mellon Virtual Memory

22 Carnegie Mellon Virtual Memory Paging Physical Memory Virtual Memory

23 Carnegie Mellon Dynamic Address Translation

24 Carnegie Mellon Files File structure  Logical storage unit  Collection of related information File System resides on secondary storage (disks) Disk provides in-place rewrite and random access  I/O transfers performed in blocks of sectors (usually 512 bytes) File Control Block – storage structure consisting of information about a file Device driver controls the physical device File system organized into layers

25 Carnegie Mellon File Control Block – File Attributes

26 Carnegie Mellon UNIX inode

27 Carnegie Mellon 1.8 Communication Networks

28 Carnegie Mellon Client-Server Models

Amdahl’s Law T : total time a : a fraction of time k : improve its performance by factor of k S : speedup

30 Carnegie Mellon Concurrency and Parallelism Thread-level concurrency Instruction-level parallelism Single-instruction, Multiple-Data (SIMD) parallelism

31 Carnegie Mellon Concurrency and Parallelism

32 Carnegie Mellon Abstractions in Computer Systems