Metrics Reporting

14 May 2023

Setting up Metric Reporting Prometheus and Grafana make a great duo for setting up system monitoring and metrics reporting on a machine. The following are my notes on how to get setup: Prometheus Prometheus is an open-source system monitoring and...

Prometheus

Grafana

Ubuntu

Getting Setup with Git

14 May 2023

My procedure for getting up and running with git Install Git: Open a terminal and type in the following command: sudo apt install git Verify the installation with: git --version This should show the installed Git version. Set up Git:...

Git

Ubuntu

The 8 Great Ideas in Computer Architecture

20 May 2020

When I studied computer architecture, I was introduced to the 8 great ideas that have resulted in much of the incredibly fast growth in computing capabilities over the past 50-ish years. They are the following: 1. Design for Moore’s Law...

Computer Engineering

Computer Architecture

PCB Debug

19 Sep 2019

The most important step in debugging is finding the correct root cause. List of possible sources of problems that can be used as a check list to review at each phase of a PCB project: Problem in the conceptual design:...

PCB Design

Electronics

Debugging

Engineering

How to Create a Self-Signed SSL Certificate

09 Aug 2019

Getting Started SSL is a cryptographic protocol that provides end-to-end encryption and integrity for all web requests. Apps that transmit sensitive data should enable SSL to ensure all information is transmitted securely. To generate our own SSL certificate, we need...

Web Servicing

Security

Storage Management

24 Jul 2019

Magnetic Media Using magnetic media, we can set a bit to 1 or 0 by applying a strong enough magnetic field to a small region of a magnetic film and this region will retain its magnetic sense even when power...

Operating Systems

Storage

Linux

PC

Thrashing

22 Jul 2019

Thrashing Thrashing describes a situation of repeated page faulting. This significantly slows down performance of the entire system and is to be avoided. It occurs when a process’ allocated number of frames is less than the size of its recently...

Operating Systems

Memory

Linux

PC

Frame Allocation

22 Jul 2019

Techniques to Improve Page Replacement Performance Use a dirty/modify bit to reduce disk writes. Choose a smart page replacement algorithm Keeps the most important pages in memory and evicts the least important. Make the search for the least important page...

Operating Systems

Paging

Linux

PC

Page Replacement Policies

20 Jul 2019

Page Replacement Policies As processes execute and bring in more pages on demand into memory, eventually the system runs out of free frames so we need a page replacement policy. Steps: Select a victim frame that is not currently being...

Operating Systems

Memory

Linux

PC

Virtual Memory

18 Jul 2019

On-Demand Paging Page tables might be large and cosume a lot of RAM. A key observation: Not all pages in a logical address space need to be kept in memory. In the simplest case, we could just keep the current...

Operating Systems

Memory

Linux

PC

Swapping, Fragmentation, and Segmentation

16 Jul 2019

Swapping If run time binding is used, then a process can be easily swapped back into a different area of memory. If compile time or load time binding is used, then process swapping will become very complicated and slow, which...

Operating Systems

Memory

Linux

PC

Memory Management

15 Jul 2019

Memory Management In the figure above, we want the newly active process P1 to execute in its own logical address space randing from 0 to max. It shouldn’t have to know exactly where in physical memory its code and data...

Operating Systems

Memory

Linux

PC

Threads

26 Jun 2019

What is a thread? A thread is a logical flow or unit of execution that runs within the context of a process. It has its own program counter (PC), register state, and stack. In addition, it shares the memory address...

Operating Systems

Processes

Linux

PC

Inter-Process Communication

24 Jun 2019

Communication between processes There are some different ways that inter-process communications are done. Signals/Interrupts Notifying that an event has occured. Message Passing Pipes Sockets Shared Memory Subject to race conditions. Synchronization Remote Procedure Calls Why use inter-process communication (IPC)? Information...

Operating Systems

Processes

Linux

PC

Processes

16 Jun 2019

What is a Process? A software program consists of a sequence of code instructions and data stored on disk; it’s a passive entity. A process is a program actively executing from main memory within its own address space. Loading Executable...

Operating Systems

Programming

Linux

PC

Loadable Kernel Modules

14 Jun 2019

Devices have both device-independent and device-dependent code There is special device driver code associated with each different device connected to the system: Device-Independent API Device-Dependent driver code Device Controller Device Independent Part a set of system calles that an application...

Operating Systems

Devices

Linux

PC

Device Strategies

12 Jun 2019

The Problem with Polling I/O We can see that the OS is spinning in a loop twice: Checking for the device to become idle. Checking for the device to finish the I/O request, so that the results can be retrieved....

Operating Systems

Devices

Linux

PC

Device Management

11 Jun 2019

Von Neumann Computer Architecture In 1945, Von Neumann described a “stored-program” digital computer in which memory stored both instructions and data. This simplified loading new programs and executing them without having to rewire the entire computer each time a new...

Operating Systems

Devices

Linux

PC

Virtual Machines

07 Jun 2019

What is a Virtual Machine? A virtual machine is a simulated computer running within a real computer. The virtual computer runs an operating system that can be different than the host OS and all the requests to access real hardware...

Operating Systems

PC

VM

Loading an Operating System

07 Jun 2019

How do we get a computer started? We have hardware and we give it power. What happens? The CPU only knows how to perform its basic operations, load, move, add, etc. The computer only does what it is told. How...

Operating Systems

PC

Linux

System Calls - How Apps and the OS Communicate

06 Jun 2019

System Calls The trap instruction is used to switch from user to supervisor mode, therby entering the OS. trap sets the mode bit to 0. On x86, use INT assembly instruction (more recently SYSCALL/SYSENTER). The mode bit is set back...

Software Engineering

Operating Systems

PC

Linux

Introduction to Operating Systems

04 Jun 2019

What is an Operating System? An operating system is a layer of software between many applications and diverse hardware that: Provides a hardware abstraction so an application doesn’t have to know details about the hardware. Otherwise an application saving a...

Software Engineering

Operating Systems

PC

VM

Magic Works With Frameworks

23 May 2019

Although there is a learning curve associated with UI frameworks such as Bootstrap and Semantic UI, the initial time investment is worth it in the end. The gained ability to create professional, clean, and aesthetically pleasing webpages in significantly less...

Software Engineering

Semantic UI

Spaceflight Influences from Film - Aliens (1986)

23 Apr 2019

The movie Aliens, directed by James Cameron and released in 1986, Is one of the most influential science-fiction films of all time. Its impact can be seen in many other works of science-fiction that have come after, including video games,...

Film

Spaceflight

Culture

Reset Changes Using Git

24 Feb 2019

Git is a version control system that can be extremely useful due to its ability to serve as a backup when something breaks. This concept is not new and has been applied to essentially every video game ever made. Analogous...

Software Engineering

Git

Magic

Mirror Git Repository With History

23 Feb 2019

Objective: Replicate state of an origin repository and mirror all history including branches to a new repository. Sometimes you may want to copy files from one repository to another and at the same time, preserve the history, branches, and all...

Software Engineering

Git

Magic

Git Good At GitHub

28 Jan 2019

For software developers, version control systems and configuration management tools such as Git and GitHub are essential assets at all levels of software development. By having a secure repository to store code with the assurance of an incorruptible “master” version,...

Software Engineering

Git

Version Control

Fly-By-Wire - An Essay

06 Apr 2018

Fly-By-Wire The Development of Digital Flight Control Computer Systems This past century has seen remarkable advancements in aviation technology and as the complexity of aircraft increased, so did the difficulty of managing the various systems that make up the aircraft....

Flight

Computer Engineering

Embedded Systems

Controls

Privacy Breaches In Code

28 Apr 2017

Engineering ethics is the set of rules and guidelines that engineers adhere to as a moral obligation to their profession and to the world. When ethics are not followed, disaster often occurs which not only includes large monetary costs and...

Software Engineering

Privacy