LoadedPrograms

[Lichtso]

Develop and Implement LoadedPrograms, replacement for the executor cache

• One global loaded programs cache per validator with two index levels: Program address and effective slot
• One local loaded programs cache per transaction batch
• Each entry has a deployment slot (making this a bitemporal model)
• And an effective slot, which does not refer to a specific block but all future blocks beyond that slot, which are descendants of the deployment slot
• Entries can hold the following types of programs:
  • LegacyV0: Programs of the legacy loader(-v1) or loader(-v2)
  • LegacyV1: Programs of the upgradeable loader(-v3)
  • Typed: Programs of loader-v4
  • Built-in
  • Tombstone: To remember that a program failed verification or was closed
  • Unloaded: To remember that a program was verified before and what usage statistics it had
  • Loading: To coordinate cooperative loading across transaction batches
• Recompilation phase before RBPF-affecting features activate to amortize workload on epoch boundary
• Delay visibility: Avoids pipeline stalls as the very next instruction in a transaction could depend on a redeployment
• Redeployment cool down: Prevents multiple (un-/re-)deployments of the same program in a slot
• Usage statistics: Kept in atomic counters in the program which itself lives in an Arc
• Simplify the transaction loader to deduplicate all accounts and not keep duplicate program accounts
• Does not care about the dependency graph in between programs, all transitive dependencies need to be specified in a message

[IntokuSatori]

Working on: https://github.com/IntokuSatori/kanonsolana/tree/dev/PR-29803