RAID 3 (Redundant Array of Independent Disks) Explained



What is RAID 3?

RAID 3 is a RAID implementation that uses striping with a dedicated parity disk.

Data is striped into blocks and distributed to the disks that make up the array. But parity information is stored in one dedicated disk.

How Does RAID 3 Work?

How Does RAID 3 Work?

RAID 3 is a RAID configuration that uses byte-level stripping for data storage. However, unlike a RAID 5 array, it uses a dedicated disk to store parity information generated by the RAID controller.

In a RAID 3 implementation, data configuration are divided into individual bytes. They are and then saved on a disk. Parity byte is determined for each row of data and saved on the the parity disk.

From the diagram above, data is divided into blocks 1a, 1b and 1c. The parity for that row is stored in block 1 parity.

RAID 3 Performance

In practice this RAID level is rarely used. One major drawback is that it cannot service multiple simultaneous requests. This is because a single I/O (input/output) operation requires a simultaneous spin of all the disks in the array.

For this reason, RAID 3 is suitable for applications that require high data transfer rates. A good example is video editing or media streaming.

Advantages and Disadvantages

One advantage of RAID 3 is its Read performance. Unfortunately, the Write performance is not as good. The need to calculate parity checksum considerably slows down the array.

With regards to disk failure, this RAID level offers the ability to recover from a single drive failure.

As per application suitability, this RAID level does not work well with applications that require simultaneous small data requests. This is due to the limitation of storing parity information in a single disk. However, as I pointed out earlier, it works well for applications that require long sequential reads and writes.

Based on these drawbacks, RAID 3 is suitable in situations where a small number of users require access to very large files.


This quick guide discussed RAID 3; how it works, its benefits and disadvantages. In practice this RAID level is not used. It was replaced by RAID 5.

I hope you found this guide useful. If you have any question or comment use the “Leave a Reply” form at the end of this page. You could also share your experience or thoughts.

Other Helpful Guides

Additional Resources and References


Please enter your comment!
Please enter your name here


network discovery keeps turning off server 2016

How to Fix Network Discovery If it Keeps Turning Off in Server 2016

Does network discovery keep turning off in your Windows server 2016? It is likely that one of its dependent services is not...
how to install windows 10 1903 update manually

How to Install Windows 10 1903 Update Manually

Windows 10 1903 Update was released in May, 2019. But some users are not yet offered the update via automatic update. The...
spotify web player not working

Spotify Web Player Not Working [Fixed]

Introduction Spotify Web Player may stop working for you with the following error messages: "Spotify Web Player an Error...
DISM.exe /Online /Cleanup-Image /Restorehealth

DISM.exe /Online /Cleanup-Image /Restorehealth Explained

What is DISM.EXE /Online /Cleanup-image /RestoreHealth? "DISM.exe /Online /Cleanup-Image /Restorehealth" is a DISM command that repairs issue with the...
DHCP Relay agent

DHCP Relay Agent: Configuration in Windows Server 2016

What is a DHCP Relay Agent? A DHCP Relay Agent allows DHCP clients in a different network subnet to...


Remote Desktop Connection

Remote Desktop Connection an Internal Error Has Occurred [Fixed]

Introduction I recently received the error message "Remote Desktop Connection an Internal Error Has Occurred". It was strange because...

Find My Samsung: Register and Use Samsung Find my Mobile

Introduction Ever wondered how you could find your Samsung phone if you lost it? Find my Samsung or Samsung...
What is the Difference Between PowerShell and CMD?

Windows Powershell vs CMD: Differences and Similarities

Introduction This short guide compares Windows PowerShell vs CMD (Windows command prompt). I will cover the history and nature...
Spotify No Longer Supports this Version of Microsoft Edge

Spotify No Longer Supports this Version of Microsoft Edge [Fixed]

Introduction When you open Spotify web player on Microsoft Edge, you may receive the error message "Spotify No Longer...
Windows 10 Won't Boot

Windows 10 Won’t Boot With Black Screen? 3 Ways to Fix It

Why Won't Windows 10 Boot Up? If your Windows 10 stops with a black screen, the first question in...


windows 10 start menu not working featured

How to Restore Windows 10 Start Menu if it Stops Working

Introduction Windows 10 start menu not working? You are not alone! A number of Windows 10 users report that...
windows update stuck featured

How to Get Windows Update to Work If Download is Stuck at 0%

Experiencing Windows Update stuck at 0%? Have you waited for hours already, yet to progress? You are not alone! A lot of...

RAID 50 vs RAID 10: Benefits and Disadvantages Compared

What is RAID 50 vs RAID 10? RAID 50 stripes two RAID 5 arrays while RAID 10 stripes two...
Benefits and Shortcomings of RAID 10

Benefits and Shortcomings of RAID 10: Quick Reference Guide

Introduction When you stripe (RAID 0) two mirrored arrays (RAID 1) arrays you produce a RAID 10. This quick...
DISM Host Servicing Process (DismHost.exe)

Dism Host Servicing Process (DismHost.exe), a Malware?

Introduction There are conflicting information about Dism Host Servicing Process (DismHost.exe). Some say it is a genuine Windows process,...


disable cortana windows 10 featured

How to Disable Cortana in Windows 10 (2 Methods)

Introduction Some Windows 10 users may not like Cortana. Solution? Disable Cortana. You are probably reading this because you...
bootrec /fixboot access is denied

How to Fix BootRec /FixBoot Access is Denied Error in Windows 10

Introduction BootRec /FixBoot Access is Denied Error in Windows 10? This error is likely caused by corrupt EFI directory.
Reset Windows 10

How to Reset Windows 10 (2 Methods)

Introduction If your Windows 10 is broken, one available way to fix it is to use Windows 10 reset....
system restore windows 10

How to Enable and Use System Restore in Windows 10

Introduction System restore in windows 10 is a very important tool that is probably ignored by most users. But...
windows has stopped this device code 43

How to Fix Windows Has Stopped this Device Code 43 Error

Introduction Sometimes you may receive "Windows has stopped this device code 43" error. This error is likely to come...
Windows could not automatically detect this network's proxy settings

How to Fix “Windows Could not Automatically Detect this Network’s Proxy Settings”

Introduction You suddenly lose the ability to connect to the internet. Then you run network troubleshooter and it returns...
printer offline

5 Ways to Restore Your Printer Online If Status is Offline

Introduction Is your printer offline? Setting it online is very simple but sometimes it is more than just setting...

How to Fix “BootMgr is Missing” Error in Windows 10

Introduction If you receive Fix "BootMgr is missing" Error in Windows 10, the default response is panic! But you...
windows 10 search featured

How to Fix Windows 10 Search If it Stops Working

Introduction Are you having troubles with Windows 10 search? Apparently, it is a fairly common problem with a number...
oooops, something went wrong. reload

How to Fix “Oooops something went wrong. reload” Spotify Error

Introduction If you receive "Oooops something went wrong. reload" Spotify error, do not panic. The fix is simpler than...


Spotify No Longer Supports this Version of Microsoft Edge

Spotify No Longer Supports this Version of Microsoft Edge [Fixed]

Introduction When you open Spotify web player on Microsoft Edge, you may receive the error message "Spotify No Longer...
bootrec /fixboot access is denied

How to Fix BootRec /FixBoot Access is Denied Error in Windows 10

Introduction BootRec /FixBoot Access is Denied Error in Windows 10? This error is likely caused by corrupt EFI directory.
powershell help

Get-Help Command: Syntax, Parameters, Examples

Introduction Don't know how to use a PowerShell cmdlet? PowerShell Get-Help cmdlet will give you information about any powerShell...
how to merge cells in excel

How to Merge Cells in Excel in 2 Easy Ways

Introduction You can merge two Cells in Excel using CONCATENATE function or the “&” (ampersand) operator. Though Excel has...
Transfer Schema Master Role

Transfer Schema Master Role With MMC or NTDSUTIL Command Tool

Introduction There are situations when an administrator may need to transfer the schema master role from one Domain Controller...

By using this website you agree to accept our Privacy Policy and Terms & Conditions