proof of concept: faster pid in sequencer

[angel-ding-cb]

Description
This PR introduces a hierarchical PID controller system to replace EIP-1559's simple proportional control with sophisticated real-time base fee management. The fast layer (sequencer) provides immediate response to gas utilization changes, while maintaining compatibility with existing batcher coordination.

Problem
Current EIP-1559 implementation on Base suffers from:

• Slow response: Takes too long to adjust to demand spikes
• High volatility: ±60% fee swings during congestion
• Poor user experience: Transactions fail during rapid fee changes
• Inefficient resource usage: Cannot handle burst capacity effectively

Solution
Hierarchical PID Controller System with two coordinated layers:

A. Fast Layer (Sequencer) - This PR
Real-time base fee adjustment in op-geth

• Location: op-geth sequencer
• Input: Gas utilization vs target
• Output: Immediate base fee adjustments
• Frequency: Every 2-second block
• Logic: Local PID based on execution capacity

B. Slow Layer (Batcher) - Future Integration
Strategic DA cost management in op-batcher

• Location: op-batcher
• Inputs:
  • DA sliding window (10MB/10 blocks)
  • L1 gas prices
  • Batch economics
  • Historical patterns
• Output: Parameter updates to sequencer via RPC
• Frequency: Every 20-60 seconds
• Logic: Combined PID considering all L1/DA constraints

Tests

some basic unit tests and integration tests are written just to test the expected behavior of the pid control

Additional context

Metadata