On September 14, 2023, Lightbits Labs, a pioneer in NVMe® over  TCP (NVMe/TCP) technology, announced that  Lightbits version 3.4.1 is now running completely in userspace, without any kernel changes required. This marked a significant leap in our path to enhance performance and versatility in storage solutions.

The standout feature of this release is Lightbits’ groundbreaking transition to full userspace operation, completely eliminating Linux kernel dependencies for the very first time. We have ported Lightbits kernel code to userspace and optimized it, ensuring that every feature functions flawlessly.

While v3.4.1 marks the initial public release of Lightbits in userspace, it has undergone rigorous testing on our internal Lightbits production servers for several months, and we are confident in its maturity. Taking advantage of the port to userspace, this release extends compatibility to new distributions – including RHEL 9.3, Alma Linux 9.3, and Rocky Linux 9.3 – and makes upgrades simpler and faster.

Additionally, this transition allows for improvements in other areas of the product such as upgrades. With Lightbits version 3.6.1, released on January 1, 2024, we are excited to announce lightning-fast upgrades.

From Kernel to Userspace: A Game-Changing Transition

Previously, Lightbits’ technology was anchored in kernel space, limiting us to specific operating systems and kernels. With the move to userspace, we broke these barriers, achieving kernel and OS agnosticism. This shift not only broadens the scope for diverse setups and configurations but also aligns Lightbits with the latest kernel versions, ensuring timely security updates without dependency on proprietary OS solutions.

Now with the kernel dependency removed, Lightbits offers lightning-fast upgrades without the requirement to reboot each server.


Userspace: Providing Flexibility and High Performance

The core of Lightbits’ promise lies in delivering unparalleled NVMe performance. The transition to userspace maintains this commitment. Our recent performance benchmarks – conducted in Azure environments – attest to this.

These benchmarks reveal that userspace performance mirrors our established kernel space performance, with the added advantage of higher bandwidth at larger block sizes. This correlation underscores our commitment to maintaining performance standards while enhancing system flexibility and security.


Understanding the Impact on Performance

comparative performance metrics in userspace versus kernel space


The chart above illustrates the comparative performance metrics in userspace versus kernel space. Note the close correlation in performance metrics, with a notable increase in bandwidth efficiency at higher block sizes when running in userspace. This increase arises from implementing additional optimizations that were previously unattainable.

Understanding the Impact on Upgrades

Upgrades from Lightbits version 3.6.1 and above no longer require full server restarts. Instead, the upgrade orchestrates service restarts such that the old Lightbits code stops and the new one starts.

With this improvement, upgrades are up to 3x times faster. In a recent test, for example, instead of taking 12 minutes per server, each server upgrade took four minutes. This meant a total cluster upgrade in 12 minutes. During this entire upgrade, the clients were completely unaware of the operation and continued to receive and transmit I/O operations without any interruption.

Why Userspace and Fast Upgrades Matter for Your Business

The introduction of userspace in Lightbits 3.4.1 and fast upgrades in 3.6.1 represents more than a technological advancement; it’s a strategic asset for businesses seeking the following:

  • OS and kernel independence
  • Compatibility with the latest security standards
  • Uncompromised NVMe/TCP performance
  • Enhanced configuration flexibility
  • Enhanced scalability by offering easier deployment configurations
  • A streamlined upgrade process and shortened maintenance windows.



At Lightbits Labs, we’re continually pushing the boundaries of NVMe/TCP technology. Userspace is more than a feature—it’s a testament to our commitment to innovation, security, and performance. Join us on this journey towards a more flexible, robust, and efficient data storage future.

Take the Next Step with Lightbits

Interested in harnessing the power of Lightbits Userspace for your enterprise? Our Sales team is ready to guide you through configuring the ideal solution tailored to your needs. Contact us today to explore how Lightbits can revolutionize your storage infrastructure.

Contact Information: Kostia Khlebopros, Senior Customer Success Engineer @ Lightbits Labs:

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