SALT Buckets

Control SALT bucket capacities to test dynamic storage gas pricing.

MegaETH uses SALT buckets to dynamically scale storage gas costs. Each account and storage slot maps to a SALT bucket; the gas cost of storage operations is multiplied by a factor derived from the bucket's capacity. Crowded state regions become progressively more expensive, while fresh storage (minimum-sized buckets) is free.

The --bucket-capacity flag lets you configure bucket capacities for testing how storage gas costs behave under different state conditions.

Options

Flag	Default	Description
--bucket-capacity <ID:CAPACITY>	empty	Set bucket capacity (repeatable)

Format: bucket_id:capacity, where:

• bucket_id — 32-bit bucket identifier

• capacity — current capacity in bytes

Examples

# Single bucket
mega-evme run contract.hex --bucket-capacity 123:1000000

# Multiple buckets
mega-evme run contract.hex \
  --bucket-capacity 123:1000000 \
  --bucket-capacity 456:2000000 \
  --bucket-capacity 789:500000

# Combined with state and tracing to observe gas costs
mega-evme tx \
  --receiver 0x1234... \
  --input 0x55... \
  --bucket-capacity 1:1000 \
  --trace --tracer opcode

Notes

• Without any --bucket-capacity flags, all buckets default to the minimum size, which means storage operations incur zero storage gas.

• This option is available in all commands (run, tx, and replay).

• SALT-based dynamic gas pricing is active in MiniRex and later specs. In Equivalence mode, bucket capacities have no effect.