XDP on Solana

XDP: High-Performance Networking for Solana Validators

May 29 2026 • Solana Foundation

XDP (eXpress Data Path) is a high-performance networking technology from the Linux kernel that allows Solana validators to process network packets significantly faster. By bypassing normal kernel network processing, data flows more directly between the network card and validator software. The efficient data processing using XDP reduces latency by up to 200x on Solana.

Agave 4.0.0 and later versions supports XDP for block propagation. Agave validator clients must explicitly enable the feature. The Firedancer client uses XDP by default.

What is XDP?

The Linux kernel's normal networking stack is designed for flexibility and generality. The kernel's networking logic adds overhead that does not impact most applications significantly, but high performance applications, like Solana, can be constrained by the kernel code.

XDP hooks into the kernel at the earliest possible point, before the packet reaches the network stack. XDP allows programs to make routing decisions in nanoseconds. For Solana validators, this means blocks are shared with the network faster, propagate faster, and the validator can respond faster.

Think of XDP as a shortcut that bypasses many layers of normal network processing. The tradeoff is that it requires specific kernel support and compatible network hardware. Solana validator operators are accustomed to high performance computing and are already adopting the new feature.

Impact on Block Propagation

Testing showed that XDP is a key enabler for consistently producing 100M compute unit blocks. With enough top validators on the network running XDP, block propagation is fast enough for the network to easily handle larger block sizes.

While XDP is not a protocol change and did not require a network upgrade, validator adoption was critical. Activating the 100M CU feature waited until engineers saw block propagation improvements in the network from widespread XDP adoption. That milestone has been reached: more than 70% of mainnet stake runs XDP, and 100M CU blocks went live on mainnet on July 29, 2026.

Agave: How to Enable XDP

XDP is supported in Agave 4.0.0+ but must be enabled by the validator operator. Follow the official Anza setup guide to configure your system:

Agave XDP Setup Guide →

The guide covers:

• Compatible Linux kernel versions and network hardware
• Kernel configuration requirements
• Agave startup flags to enable XDP
• How to verify XDP is active on your validator

XDP will be on by default in Agave 4.2.

Firedancer: Enabled by Default

The Firedancer validator client has used XDP since its inception. XDP is the default networking mode. Firedancer was designed from the ground up to take advantage of kernel-bypass networking.

If you are running Firedancer, no action is needed. XDP is already active.

Why This Matters

The Solana protocol is rapidly pushing the boundaries of bandwidth and performance. The Solana block size limit is now 100M CUs, a 66% increase over the previous 60M CU limit. At the previous block sizes, the block propagation layer of the protocol was not constrained.

At 100M CUs, Turbine, the block propagation layer of the protocol, would have become the network bottleneck without faster networking. Larger blocks mean more data is being sent to thousands of machines every second. XDP is the key improvement that enables Solana to easily handle 100M CU blocks. Larger block capacity enables real world use cases like trading and payments.

Summary

XDP is a linux kernel networking technology. Solana validator clients leverage XDP to enable much higher performance networking, which allowed for a 66% increase in block capacity to 100M CU blocks.

Learn more: Solana Upgrades