ReFS vs NTFS File System | Pros, Cons & Differences

Case: ReFS vs NTFS?

ReFS (Resilient File System) and NTFS (New Technology File System) are both file systems used in Windows operating systems. Every day, you generate or access large amounts of data that stored on disk in the form of files. A better file structure can provide greater accessibility, security, and optimal performance. That's why Windows introduced ReFS file system with Windows Server 2012 to iterate on NTFS.

That makes you now have 2 file system you can choose from, ReFS and NTFS. And both of them work well with type-1 hypervisor Hyper-V VM storage. However, they have some differences in terms of their features and capabilities. So, how do you choose NTFS or ReFS? This article will introduce them respectively and compare NTFS vs ReFS to help you make the right choice.

What is NTFS

NTFS (New Technology File System), first introduced in 1993 with Windows NT operating system (OS) version 3.1, is a proprietary journaling file system for efficiently storing, organizing, and retrieving files on the hard disks.

With better scalability, interoperability, security, and performance, NTFS superseded FAT (File Allocation Table) as the preferred filesystem on Windows, and is supported in Linux and BSD as well. By using the convert command, Windows can convert FAT32/16/12 into NTFS without the need to rewrite all files

Advantages

• Journaling: NTFS uses log file to record metadata changes to the volume, and restore the consistency of the file system (restore data) when the computer is restarted after a system failure. After a bad-sector error, NTFS dynamically remaps the cluster that contains the bad sector, making bad cluster and allocating a new cluster for the data.
• Security: NTFS uses Access Control Lists (ACLs) and user-level encryption to help secure user data. You can set permissions on files or folders, specify the groups and users who access you want to restrict or allow, and select access type. Or you can also provide user-transparent encryption of any file or folder on an NTFS volume.
• System resource saving: Features such as File system compression, hard links, and disk quotas can effectively conserve system resources and storage system disk space.

Disadvantages

• Compatibility: the main disadvantage of NTFS is limited compatibility of non-Windows operating systems and removable devices support, for example, Mac OS computers can only get written to NTFS formatted drives with the help of third-party software, removable devices and media devices such as Android smart phones and digital cameras do not support NTFS storage devices.

What is ReFS

ReFS (Resilient File System), first introduced with Windows Server 2012, is an advanced file system type that can store large amounts of data in a safe way.

ReFS file system was intended to become the next generation file system after NTFS, therefore it addressed some of the issues that the NTFS system encounters. For example, the compatibility of different storage scenarios, data integrity with resiliency to corruption, and maximum data availability to scale to large data sets across diverse workloads efficiently.

Advantages

• Resiliency: ReFS has the built-in resilience to check files as you read or write them to ensure that there is no data corruption, without using chkdsk. Meanwhile, the data integrity scanning program will regularly check all files on the drive to recognize and fix the corrupted data. This provides higher integrity and availability for data.
• Scalability: ReFS can support extremely large amounts of data, with a theoretical maximum capacity of 262,144 EB. And ReFS supports up to 32,768 characters in a file name and file path by default.
• Performance: ReFS’s mirror-accelerated parity feature allocates data across two different tiers on the drive, to enable high performance and efficient data storage. Writing to disk quickly in the mirror tier to accelerate file read and write times, and then transfers data to the parity tier to recompute each written file and make more efficient use of disk space.

Disadvantages

• Windows boot: Windows cannot boot from ReFS and require NTFS.
• Resources consuming: ReFS consumes more system resources, compared with NTFS. And the bigger the disk array, the more RAM and IOPS ReFS uses for file integrity.
• Data conversion: NTFS data cannot be converted to ReFS.
• Features: ReFS does not include features like file system compression and encryption, hard links, extended attributes, data deduplication, and disk quotas.

ReFS vs NTFS: features and performance

While ReFS is made up from the current NTFS file system code and has borrowed most of its functionality from NTFS, they are still very different in terms of functionality and applicable scenarios. Therefore, ReFS is currently not a complete replacement for NTFS.

Comparing ReFS vs NTFS, there are 5 main differences:

• Scalability: ReFS is more easily scalable than NTFS and ensures an efficient storage performance. NTFS theoretically provides a maximum capacity of 16 exabytes, while ReFS has 262,144 exabytes. And the maximum file path length in NTFS is 255 characters, whereas the maximum path length in ReFS is 32,768 characters.
• Reliability: ReFS and NTFS differ in the way they protect storage and ensure data integrity. NTFS uses log files and checkpoints so that in the event of a system failure, you can manually check the disk and restore the disk infrastructure to the previously recorded version. ReFS, on the other hand, checks every file when reading and writing files, and has automated this process. even in the event of a power failure, ReFS can effectively prevent data loss.
• ReFS vs NTFS Performance: ReFS has higher performance than NTFS, especially when being used with virtual machines. NTFS improves performance with features such as disk quotas, file compression, and resizing, but ReFS’s mirror-accelerated parity provides even better performance and more efficient storage. In addition, ReFS provides better performance and functionality for virtual machines with support for block cloning and sparse VDL (Valid Data Length).
• Compatibility: While NTFS is compatible with all versions of Windows, ReFS is only compatible with newer versions of Windows, such as Windows Server 2012 and Windows 8.1 or later.
• Features: Although ReFS has advantages such as automatic integrity checking and data scrubbing, elimination of the need for running chkdsk, and storage virtualization and pooling, etc over NTFS, there are many NITS features are not implemented in ReFS.

Here is a table shows how ReFS vs NTFS are different in their features.

Note: ReFS’s File-level snapshots are only available on Windows Server 2022 and later. For details, you can refer to Microsoft’s official document: Resilient File System (ReFS) overview

Summary

As Microsoft’s proprietary file system, both NTFS and ReFS are widely used today. This article introduced what NTFS and ReFS are respectively, and compared ReFS vs NTFS to show the differences.

As the expected next generation of NTFS, ReFS are still not the perfect replacement for NTFS. They are very different in features which makes them suitable for different scenarios. If you are looking for a choice for your Hyper-V VM file-level storage, you may consider ReFS for its advanced features in enhancing performance and functionality of Hyper-V VM.