Author: Toufeeq
Technical Summary
This AIP proposes a set of network parameters and node configuration updates that have already been deployed and validated on the Turing testnet. These updates aim to improve block finality times, increase block capacity at the node level, and enhance network resilience during temporary finality stalls. The key changes are:
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Decrease finality gap from 2 blocks to 1 block from the best block, enabling blocks to finalise in ~20 seconds (down from ~40 seconds).
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Increase supported block size in the node binary up to 64 MiB, allowing for significantly higher data throughput and scalability.
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Update block authoring backoff strategy to limit the maximum delay to 5 minutes during finality stalls, preventing extended authoring inactivity.
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Increase the number of primary slots to a probability of 1/3 (from 1/4), improving slot utilisation and reducing missed block production when some validators are offline.
Motivation
These proposed updates are part of the ongoing optimisation of Avail’s consensus and data-availability layers to support larger workloads, faster confirmations, and smoother authoring behaviour under varied network conditions.
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Faster Finality:
Reducing the finality gap from 2 → 1 block allows GRANDPA to finalise blocks roughly twice as fast, cutting the perceived finality latency from ~40 seconds to ~20 seconds.
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Higher Block Capacity:
Increasing block size support to 64 MiB prepares Avail for future data-heavy use cases and scaling tests.
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Authoring Stability During Finality Stalls:
The revised backoff mechanism (capped at 5 minutes) ensures nodes resume block production promptly even when finality temporarily stalls, improving overall network liveness.
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Improved Slot Coverage:
Adjusting the probability of primary slots from 1/4 to 1/3 reduces the likelihood of missed slots when a subset of validators is down, improving block production consistency.
Rationale and Reasoning
All proposed changes have been successfully tested and validated on the Turing testnet under realistic network conditions. The results demonstrated:
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No degradation in block propagation or finality metrics at higher block sizes.
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Stable validator performance and resource usage during increased load.
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Significant improvement in block finalisation speed, now consistently around 20 seconds.
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Reduced missed-slot occurrences under partial validator downtime scenarios.
These adjustments ensure that Avail remains performant, responsive, and ready for scaling use cases that demand higher throughput and reduced confirmation latency.
Security Considerations or Risks
Testing on Turing confirms that these updates introduce no additional security or stability risks.
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The finality gap reduction maintains safety guarantees of GRANDPA while improving finality.
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Larger block size support only expands node capacity limits and does not alter consensus rules.
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The backoff cap ensures predictable authoring recovery
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Adjusted slot probabilities retain fairness while improving overall slot utilisation.
The first three changes can be enacted through a binary release, while the fourth requires a governance proposal to update the relevant runtime configuration parameters.
Copyright Waiver
Copyright and related rights waived via CC0.