RPC (Remote Procedure Call) infrastructure serves as the communication gateway between applications and the Solana cluster. These requests are handled by specialized RPC nodes, which are dedicated servers optimized for processing these interactions. While they don't participate in Solana's consensus mechanism, RPC nodes are critical for ensuring smooth application performance.

From a user’s perspective, poor RPC performance feels identical to cluster inefficiency, making a well-optimized RPC setup essential for showcasing Solana's speed and low-latency promise.

Development and Best Practices

Using Local Clusters

• Purpose: Ideal for early development and testing.

• Advantages:

  • Greater flexibility for running unoptimized versions.

  • Cost-effective and localized control.

• Tool:
  Use the solana-test-validator binary included in the Solana CLI Tools for setting up local clusters.

Optimizing RPC Requests

Minimize Redundancy

• Avoid frequent, repetitive calls for the same data.

• Optimize costly calls like:

  • getProgramAccount

  • getSignaturesForAddress2

  • getConfirmedBlock

Use Backends Effectively

• "Backend-less dApps" are misleading, as they often burden someone else's infrastructure.

• Build backends to:

  • Aggregate requests.

  • Cache results for reuse.

Caching

• Cache expensive RPC calls in ways optimized for your application.

• Serve users from the cache when possible, reducing strain on infrastructure.

Code Optimization

• Focus on optimization before going live to:

  • Reduce infrastructure costs.

  • Improve user experience.

RPC Services

Free RPC Services

Features:

• Provided by third-party RPC providers for public Solana clusters.

• Suitable for:

  • Testing.

  • Early-stage demos.

  • Private beta programs.

Limitations:

• Rate-limited and non-scalable.

• No guarantees or SLAs.

• Risk of bans for overuse.

Private RPC Services

When to Use:

• For applications that are publicly available or need to handle significant traffic.

Advantages:

• Autoscaling capabilities.

• Service guarantees (SLAs).

• Reliable performance under heavy loads.

Recommendation: Transition to private RPC services as soon as the application is ready for production to avoid user experience degradation.