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A Raspberry Pi dashcam with two cameras and a GPS

28/09/2015 Comments off

Information on how to set up a Raspberry Pi as a two cameras dashcam with GPS.

General information about the Raspberry Pi dashcam

  What was used and how it’s connected up.

  Installing Arch Linux or Raspbian, resize the SD card, camera configurations etc.

How to wire up the button, LEDs and GPS using the Pi’s GPIO pins
A simple button for shutdown / reboots, status LEDs and an easy to connect GPS.

The built-in version

  I decided to try and hide things away and make it automated.
  Current status. What next?

Here are a couple of videos of the dashcam in action…

  
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Linux and Unix Test Disk I/O Performance With dd Command

24/09/2015 Comments off

Source: nixCraft

How can I use dd command on a Linux to test I/O performance of my hard disk drive? How do I check the performance of a hard drive including the read and write speed on a Linux operating systems?

You can use the following commands on a Linux or Unix-like systems for simple I/O performance test:

dd command : It is used to monitor the writing performance of a disk device on a Linux and Unix-like system.

hdparm command : It is used to get/set hard disk parameters including test the reading and caching performance of a disk device on a Linux based system.

In this tutorial you will learn how to use the dd command to test disk I/O performance.

Use dd command to monitor the reading and writing performance of a disk device:

  1. Open a shell prompt.
  2. Or login to a remote server via ssh.
  3. Use the dd command to measure server throughput (write speed)
dd if=/dev/zero of=/tmp/test1.img bs=1G count=1 oflag=dsync
  1. Use the dd command to measure server latency
dd if=/dev/zero of=/tmp/test2.img bs=512 count=1000 oflag=dsync

Lire la suite…