Protocol Quebec

This page lists the changes brought by protocol Quebec with respect to Paris (see Protocol naming). For the list of changes brought by Paris with respect to Oxford, see Protocol Paris.

For a higher-level overview of the most salient new features see the Quebec announcement.

The code can be found in directory src/proto_021_PsQuebec of the master branch of Octez.

Environment Version

This protocol requires a different protocol environment version than Paris. It requires protocol environment V13, compared to V12 for Paris.

• Removed the 4th version of the WASM PVM, added the 5th version of the WASM PVM. (MR !12999)

Smart Rollups

• Michelson values of type contract _ are now allowed in messages exchanged between smart contracts and smart rollups. In particular, it is now possible for smart rollups to use typed callbacks in outbox messages. (MR !11130)

• Bumped WASM PVM to V5. (MR !12999)

• Reworked constants migration to preserve the various period duration instead of indiscriminately imposing them (e.g., imposing 2 weeks for the challenge window or 15 minutes for the commitment period). (MR !13821)

• Fixed the traversal logic of the commitments tree, by considering previous commitment periods when computing what should be the level of a commitment successor. (MR !13841)

Data Availability Layer

No changes.

Adaptive Issuance

• Added the Adaptive Maximum system, that imposes a new bound on the issuance as a function of the staked ratio. (MRs !13519, !14635)

• Changed the semantics of the min-delegated-in-current-cycle used to compute baking rights. It now only considers the minimum in between blocks. (MR !13945)

• Changed the protocol constant value of edge_of_staking_over_delegating from 2 to 3. (MR !14555)

• Bumped the GLOBAL_LIMIT_OF_STAKING_OVER_BAKING protocol constant from 5 to 9. (MR !14905)

Gas improvements

• Updated a few gas parameters to be more accurate. (MR !13171)

Breaking Changes

• Reworked RPC GET /chains/<chain_id>/blocks/<block_id>/context/delegates/<baker_pkh>, which returns a lot of information about a given baker. Its fields now match all non-deprecated delegates/<baker_pkh>/... RPCs one-for-one. This change is breaking for both JSON and binary encodings. (MR !14209)

RPC Changes

• In the following paths, ../ is short for /chains/<chain_id>/blocks/<block_id>/context/delegates/<baker_pkh>/. See Baking Power for more details on the renamed and new RPCs.

  • Renamed RPC GET ../current_frozen_deposits to GET ../total_staked. The old path is now deprecated. (MR !14176)

  • Added RPC GET ../total_delegated, which returns the amount that counts as delegated to the baker for the purpose of computing its baking rights. This includes tez owned by all delegators including the baker itself, but excludes staked tez. (MR !14176)

  • Deprecated RPC GET ../staking_balance. To get its value, you can call RPCs GET ../total_staked and GET ../total_delegated, and add their outputs together. (MR !14176)

  • Renamed RPC GET ../total_delegated_stake to GET ../external_staked. The old path is now deprecated. (MR !14187)

  • Added RPC GET ../external_delegated, which returns the amount of non-staked tez owned by all delegators except for the baker itself. (MR !14187)

  • Deprecated RPC GET ../delegated_balance. To get its value, you can call RPCs GET ../external_staked and GET ../external_delegated, and add their outputs together. (MR !14187)

  • Deprecated RPC GET ../frozen_deposits. To get its value, you can call RPCs GET ../total_staked on the last block of 3 cycles ago. (MR !14192)

  • Deprecated RPC GET ../frozen_deposits_limit. The RPC has no effects since the activation of Adaptive Issuance and Staking during the Paris protocol. (MR !14192)

  • Renamed RPC GET ../current_baking_power to GET ../baking_power. The old path is now deprecated. (MR !14192)

  • Renamed RPC GET ../delegated_contracts to GET ../delegators. The old path is now deprecated. (MR !14192)

  • Renamed RPC GET ../full_balance to GET ../own_full_balance. The old path is now deprecated. (MR !14154)

  • Added RPCs GET ../own_staked and GET ../own_delegated. They are similar to total_staked and total_delegated, except that they only consider tez owned by the baker itself. (MR !14244)

  • Renamed RPC GET ../unstaked_frozen_deposits to GET ../total_unstaked_per_cycle. The old path is now deprecated. (MR !14244)

• In the following paths, ../ is short for /chains/<chain_id>/blocks/<block_id>/context/contracts/<contract_id>/.

  • Added RPC GET ../spendable which is identical to GET ../balance. (MR !14154)

  • Added RPC GET ../spendable_and_frozen_bonds which is identical to GET ../balance_and_frozen_bonds. (MR !14154)

• Reworked RPC GET /chains/<chain_id>/blocks/<block_id>/context/delegates/<baker_pkh>; see Breaking Changes.

Errors

• The validate.operation.inconsistent_sources and validate.operation.inconsistent_counters errors have been expanded with information on the problematic sources and counters. The error messages have been updated accordingly, but the error IDs remain unchanged. (MR !13138)

8s Blocks Time (MR !12716)

Blocks time have been reduced from 10 seconds to 8 seconds. That is, a block can be produced with a delay of 8 seconds with respect to the previous block, if both blocks have round 0. This change comes with updating many related protocol parameters in order to match the reduced blocks time. In particular, the following quantities are kept the same:

• the minimal time period of a cycle (namely, 2 days, 20 hours, and 16 minutes),

• the length of the nonce revelation period (namely, around 2 hours and 8 minutes)

• the number of nonce commitments per cycle (namely, 128),

• the maximum rewards per minute (namely 80 tez), and therefore roughly the same issuance,

• the minimal “time to live” of an operation (namely, 1 hour),

• the block gas limit per minute (namely, 10400000 gas),

• the ratio between the liquidity baking subsidy and the maximum rewards per block (namely, 1/16).

Changes to protocol parameters

Parameter (unit)	Old (Paris) value	New value
minimal_block_delay (seconds)	10	8
delay_increment_per_round (seconds)	5	4
blocks_per_cycle (blocks)	24576	30720
blocks_per_commitment (blocks)	192	240
nonce_revelation_threshold (blocks)	768	960
max_operations_time_to_live (blocks)	360	450
hard_gas_limit_per_block (gas unit)	1733333	1386666

Internal

• balance_update_encoding_with_legacy_attestation_name has been removed. (MR !13461)

• Encoding that supports endorsement kind in apply_result JSON has been removed. (MR !13974)

• Encoding that supports endorsement kind in operation JSON has been removed. (MR !13976)

• Moved the RPC files contract_services.ml* and delegate_services.ml* from lib_protocol to lib_plugin. (MR !14094)