User and System Time in MT programs

User and System Time in MT programs - User and System Time...

Info icon This preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
User and System Time in MT programs Command “time” gives User Time = Time spent in user mode System Time = Time spent in Kernel mode Real Time = wall clock time. In a single processor machine User time + system time < Real time Why? Overhead of other programs running in the same machine.
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
User and System Time in MT programs In a multi processor machine User time + system time < N* Real time Where N is the number of processors
Image of page 2
Atomic Sections in Java In Java atomic sections are implemented using the “synchronized” keyword. No explicit calls to mutex_lock()/mutex_unlock() are needed. Any Java object can serve as a lock. Java implements synchronization in three ways: Synchronized Class Method Synchronized Instance Method Synchronized Statement
Image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Synchronized Class Method All the statements in the method become the atomic section (synchronized block) and the Class object is the lock. class class_name { static synchronized type method_name() { statement block } } All static synchronized methods in the class are
Image of page 4
Image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern