COMS 4118 (Operating Systems I)

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COMS 4118 (Operating Systems I)

• Henning Schulzrinne
• Dept. of Computer Science
• Columbia University
• http//www.cs.columbia.edu/hgs

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Course mechanics

• Instructor hgs4118_at_cs.columbia.edu
• My office hours Tuesdays, 4-5 pm, 450F CSB or by
  appointment
• please contact Rosemary Addarich
  (rosemary_at_cs.columbia.edu)
• check MICE for exceptions
• TA Zhiyang Cao
• office hours Wednesdays, 3-5 pm or by
  appointment
• Web page --gt basics, assignments
• http//www.cs.columbia.edu/hgs/teaching/os
• Wiki --gt hints, assorted documents
• Assignment upload, slides and mailing list via
  Courseworks
• Will set up bulletin board for discussions

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Structure of course

• Lectures - book material background
  discussion
• Homework assignments
• Midterm, final

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Prerequisites

• CSEE W3827 (Fundamentals of Computer Systems)
• understanding of computer system architecture
• registers, cache, virtual memory, I/O, DMA,
  disks, etc.
• interrupts
• basic knowledge of what assembly language is
• COMS W3157 or W3101
• understand how to use make, C compiler, gdb,
• The C programming language
• Java is also helpful

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Course outline topics

• Overview and history
• Computer organization
• VMWare Linux kernel tutorial
• Processes
• IPC
• Threads
• CPU scheduling
• Synchronization
• Multi-processor systems

• Memory management
• I/O
• Disks and scheduling
• File systems
• Protection security
• Networking
• Distributed systems

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The deal

• Your responsibility
• youre all adults
• responsible for your own actions and scheduling
  choices
• if you dont understand something, ask
• Please note academic honesty policy
  http//www.cs.columbia.edu/education/honesty
• discussion with others is encouraged - study
  groups, discussion board, etc.
• zero tolerance for cheating or outsourcing
  homework
• well clearly identify group work
• lock your files -- just looking is not
  acceptable
• Our responsibility
• be responsive to your questions
• try to fix problems

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Lectures

• Slides for each class
• derived from book slides, but modified and
  enhanced
• Uploaded to Courseworks shortly before class
• sometimes updated after class
• Class is on CVN
• on-campus students can watch
• after add/drop period

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Assignments Grading

• Grading
• 50 assignments
• 20 midterm (closed book)
• 30 final (cumulative, closed book)
• 0 no extra credit work
• will be curved
• 6 written assignments (every two weeks)
• individually solved
• alternate with 6 Linux kernel assignments
• groups of 3, all with the same score
• each participant rates the others
  non-contributors will be voted off the island
  (onto their own island of like-minded slackers)
• Late policy
• five late days
• late assignments will not be graded, but you can
  submit partial assignments
• at noon on due date

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Programming assignments

• All programming assignments must be in C
• Java, C, Fortran, are not acceptable
• unless explicitly noted otherwise
• If you dont know C, come back next year
• Needed for Linux kernel (C)
• Linux kernel assignments in group
• may do small programming assignments individually

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Linux (kernel) projects
subject to change

• Shell
• Linux system call
• CPU scheduling for multimedia
• Disk paging
• Network monitoring

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Working with kernels

• Very different from standard applications
• Part of a very large system (10s MLOC)
• side effects can be unpleasant
• spend more time reading programs than writing
  them
• Debugging kernels
• long build - boot - test cycle (--gt batch jobs)
• limited debugging (printf)
• asynchronous behavior -- hard to provide right
  stimulus
• Heisenbugs

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CLIC lab

• All programs and kernels must boot run on the
  CLIC machines
• if not, zero credit
• but you can develop at home, on your laptop,
• Youll need a CLIC account
• https//www.columbia.edu/crf/accounts/
• You will be assigned a particular CLIC machine
  for virtual machine use
• Some CLIC machines are for in-person use others
  can only be accessed remotely
• No food or drink in CLIC
• be considerate -- others are trying to concentrate