Timing Subsystem in deep

Timing Subsystem in deep, available at $59.99, has an average rating of 4.5, with 98 lectures, based on 15 reviews, and has 479 subscribers.

You will learn about Programming timing in user space Timing Hardware Jiffies Low resolution & High resolution timers POSIX Clocks This course is ideal for individuals who are Linux Kernel Developers interested in gaining deep knowledge about timing subsystem It is particularly useful for Linux Kernel Developers interested in gaining deep knowledge about timing subsystem.

Enroll now: Timing Subsystem in deep

Summary

Title: Timing Subsystem in deep

Price: $59.99

Average Rating: 4.5

Number of Lectures: 98

Number of Published Lectures: 98

Number of Curriculum Items: 98

Number of Published Curriculum Objects: 98

Original Price: $119.99

Quality Status: approved

Status: Live

What You Will Learn

Programming timing in user space

Timing Hardware

Jiffies

Low resolution & High resolution timers

POSIX Clocks

Who Should Attend

Linux Kernel Developers interested in gaining deep knowledge about timing subsystem

Target Audiences

Linux Kernel Developers interested in gaining deep knowledge about timing subsystem

Timing Measurements in Linux Kernel

Many computer activities are based on timing measurements.

E.g. Your Computer display is turned off, if you have not pressed a key or moved your mouse for a particular time.

Linux timing subsystem mainly handles two types of timing activities

        1. Keeping the current time and date

                a. time() , gettimeofday() and clock_gettime()

                b. Time stamps for files and network packets

        2. Maintaining Timers

                a. Mechanisms to notify kernel and user space (ex. alarm()) that a certain interval of time has elapsed.

Hardware Devices

Linux depends on hardware devices to maintain time. These devices can be basically classified into two types:

        1. Clocks/Counters:  provide precise time measurements

                Used to keep track of current time of day

        2. Timers: Issue interrupts at fixed, predefined frequency.

                Used for implementing software timers

What will you learn from this course?

Various timing commands: date, uptime

POSIX Clocks: CLOCK_BOOTTIME, CLOCK_MONOTONIC_RAW, CLOCK_REALTIME, CLOCK_PROCESS_CPUTIME_ID, CLOCK_THREAD_CPUTIME_ID

Timing System calls: ctime, gettimeofday, clock_gettime, clock_settime, clock_getres, times, getrusage

Setting time from userspace

How to measure time for a particular instruction

Hardware Devices used in timing measurement: RTC, TSC, Programmable Interval Timer, APIC, High Precision Event Timer

Jiffies

Low Resolution and High Resolution Timers

This course comes with a 30 day money back guaranteed!.If you are not satisfied with the course, you’ll get your money back

So what are you waiting for, enroll now and take the next step in learning Timing subsystem in Linux Kernel

Course Curriculum

Chapter 1: Programming timing in user space

Lecture 1: date command

Lecture 2: uptime command

Lecture 3: Epoch time

Lecture 4: ctime

Lecture 5: gettimeofday

Lecture 6: Can gettimeofday() be used for measured elapsed time

Lecture 7: Monotonic clock

Lecture 8: CLOCK_BOOTTIME

Lecture 9: CLOCK_MONOTONIC_RAW

Lecture 10: CLOCK_REALTIME

Lecture 11: CLOCK_PROCESS_CPUTIME_ID

Lecture 12: Example to calculate time taken to increment

Lecture 13: Another Example using clock_gettime

Lecture 14: CLOCK_MONOTONIC vs CLOCK_PROCESS_CPUTIME_ID

Lecture 15: CLOCK_THREAD_CPUTIME_ID

Lecture 16: clock_settime

Lecture 17: clock_getres

Lecture 18: times

Lecture 19: getrusage

Chapter 2: Hardware devices used in timing measurement

Lecture 1: Timing Measurements in Linux Kernel

Lecture 2: RTC

Lecture 3: Kernel module example reading RTC

Lecture 4: RTC Interrupts

Lecture 5: RTC IOCTL Interface

Lecture 6: RTC Periodic Interrupts

Lecture 7: RTC Alarm Interrupt

Lecture 8: Why RTC is not used after computer is powered on

Lecture 9: TSC

Lecture 10: Reading TSC from kernel space

Lecture 11: RDTSCP

Lecture 12: Issues using TSC with multiprocessor systems

Lecture 13: Kernel functions for TSC

Lecture 14: Programmable Interval Timer

Lecture 15: Local APIC

Lecture 16: High Precision Event Timer

Lecture 17: Linux Abstraction

Chapter 3: Jiffies

Lecture 1: HZ

Lecture 2: jiffies

Lecture 3: What is the size of jiffies

Lecture 4: Why is jiffies not declared as 64-bit on x86

Lecture 5: Jiffies Wraparound

Lecture 6: What is the initial value of jiffies on boot

Lecture 7: INITIAL_JIFFIES

Lecture 8: Why double casting is needed for INITIAL_JIFFIES macro

Lecture 9: Convert jiffies to seconds milliseconds

Lecture 10: Measuring module loaded time using jiffies

Lecture 11: Can we update jiffies

Lecture 12: Timer Interrupt processing

Lecture 13: Busy looping using jiffies

Lecture 14: Jiffies conversions

Lecture 15: How are busy loops implemented

Lecture 16: What is disadvantage of having periodic interrupts in Linux Kernel

Lecture 17: Configuration of clock interrupts

Chapter 4: Low Resolution TImers

Lecture 1: Introduction to timers

Lecture 2: Implementation of low resolution timers

Lecture 3: Specifying an expiration time

Lecture 4: Which context timer handler runs

Lecture 5: Timer implementation

Lecture 6: Are interrupts disabled while running timer handler

Lecture 7: Whether timer handler runs in softirq or hardirq

Lecture 8: Whether kernel checks all timer entries on each raise softirq

Lecture 9: Deactivate a timer

Lecture 10: del_timer_sync

Lecture 11: timer_pending

Lecture 12: Periodic timers

Lecture 13: Synchronize between process context and timer handler

Lecture 14: Run timer handler every one second

Lecture 15: Timer Flags

Lecture 16: How schedule_timeout works

Lecture 17: Problems with low resolution timers

Chapter 5: ktime_t

Lecture 1: Introduction to high resolution timers

Lecture 2: ktime_t

Lecture 3: Macros and functions for ktime_t

Lecture 4: Macros and functions for add sub ktime_t

Lecture 5: ktime_t conversion functions

Lecture 6: Example of conversion functions

Lecture 7: ktime accessors

Lecture 8: ktime accessors part 2

Lecture 9: ktime accessors part 3

Lecture 10: nanosecond output

Lecture 11: timespec output

Lecture 12: seconds output

Lecture 13: How uptime is implemented

Lecture 14: How gettimeofday is implemented

Lecture 15: How clock_gettime is implemented

Lecture 16: coarse variants

Lecture 17: Why are coarse variants faster

Chapter 6: HRTimers

Lecture 1: Introduction

Lecture 2: Cancel a timer

Lecture 3: Return value of callback timer

Lecture 4: hrtimer_forward_now

Lecture 5: Measuring clock cycles

Lecture 6: Examples of clocks and modes

Lecture 7: hrtimer_callback_running

Instructors

Linux Trainer
Trainer at Linux Weekend Learning

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3 stars: 1 votes

4 stars: 8 votes

5 stars: 6 votes

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