CS170: Efficient Algorithms and Intractable Problems Fall 2001
CS170 Discussion – 2009-04-24
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Transcript of CS170 Discussion – 2009-04-24
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CS170 Discussion – 2009-04-24Bryce Boe
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Outline•Announcements•Pair Programming•Project 3 Questions•Partner Assignment
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Announcements•Project 3 Deadline extended to Friday
March 1 11:59•Late Point Deduction: 1% every 5 minutes•New rules for making patches
▫http://cs.ucsb.edu/~bboe/dynamic/170_teams#patches
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Pair Programming•2 people, 1 computer•Two Roles
▫Driver – in control of keyboard and thus for the code that get emitted
▫Observer – watches driver, plans the next steps
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Why am I talking about this?•Both members understand all changes,
thus get more out of this course•Mutual benefit of shared knowledge and
experience
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Hand-wavy statistics•~15% less efficient than two independent
developers•~15% fewer bugs produced*
•Increased enjoyment from of programming
• http://collaboration.csc.ncsu.edu/laurie/Papers/XPSardinia.PDF
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“"It's like twice the brains with half the typing!” - Jeff Browne 1st year Ph.D.
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Source: Jonathan Kupferman 1st year MS
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Pair Programming Videohttp://
agile.csc.ncsu.edu/pairlearning/educators.php
Courtesy of North Carolina State University
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Project 3 – Realtime processes•A realtime process is one that does not
get •Invoked via the syscall: enter_rt(clock_t
period)
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Notes•Steps in getting message to scheduler
▫User process makes system call▫System call is a wrapper around passing
message to the appropriate server▫The appropriate server then sends a
message to the kernel (kernel call)▫The scheduler now has it.
•Round-robin scheduling of different priorities