Reliance Nitro is the choice of leading OEMs who build devices where data reliability is critical. As the Internet of Things gives rise to more devices that capture and store data from their environment in real-time, developers are demanding systems that have the real-time features of Nucleus RTOS but also robust data storage capabilities. Reliance Nitro gives developers precise control over file system behavior to optimize performance for diverse use cases while ensuring data is free from corruption even in the event of a power failure or unexpected shutdown.

Reliance Nitro integrates with the Virtual File System (VFS) in Nucleus Ready Start, enabling developers to use Reliance Nitro as a completely reliable replacement for the default Nucleus FAT-compatible file system or run Reliance Nitro alongside it to provide enhanced reliability just for critical system and user data.

Comparison of File System Options for Nucleus RTOS

FeatureBenefitsReliance NitroNucleus FATNucleus SAFE
Transactional, atomic operations Always maintains a known-good state of the file system for fast booting and data reliability      
Extent-base Fast performance on large files      
Tree-based Fast file access regardless of media size or fullness      
Preserves file system structure File system is always available      
Preserves file data Users data is free from corruption      
Simultaneous read and write threads System does not need to suspend read operations during a write      
File level secure delete Secure data can be completely removed a file at a time rather than requiring a full media wipe, which is time consuming      
Works with any block device (ie SD/MMC, SSD, HDD, CF card, etc) Gives system designer flexibility     NAND, NOR only
Never overwrites live data Ensures user data remains valid, even if system fails during a write      
Transaction controls available at run-time Gives application developers better control over file system operation      
File data and metadata CRC Validates that what was written to the media remains correct and protects against media failures (increasingly common, especially on flash media)      
Common data format across multiple OS Lets complex devices using multiple operating systems share a data store      
Guaranteed support response time Helps keep projects on schedule      
POSIX-compliant Speeds application development      
Supports sparse files Avoids "end of file" errors      
Supports file expansion Simplifies application programming      
Operating system support   Linux, Android, Windows Embedded, VxWorks, Nucleus. Portable to others. Any OS that supports FAT


Information on non-Datalight products believed to be correct but not guaranteed.

Performance Results

Test Environment: Mistral board with TI DaVinci 8148 processor (TMDXEVM8148 EVM) with 512 MB SD card. Running FSIO test, a file system independent test suite developed by Datalight to test key parameters of file system performance, including file and directory operations and various throughput scenarios.

KB/SReliance NitroNucleus FAT
Sequential Read (Large, aligned) 2512 2489
Sequential Write (Large, aligned) 1498 1307
Random Read (Small, aligned) 2234 553
Random Write (Small, aligned) 517 166



 Reliance NitroNucleus FAT
Create 1000 files 15.2 seconds 1 minute 59.8 seconds
Open 1000 files 0.1 seconds 48.3 seconds
Delete 1000 files 10.8 seconds 1 minute, 20.6 seconds
Create directory tree 35 seconds 1 minute 45.4 seconds
Delete directory tree 11.7 seconds 1 minute 15.2 seconds