* paras: `include_pvf_check_statement` rt bench
Resolves#4933
This PR adds a benchmark for the `include_pvf_check_statement`
dispatchable. This is a necessary step to make it work without
modifications. That enables us to proceed with testing on Versi.
This introduces 5 new benchmarks. Those measure performance of the
`include_pvf_check_statement` under 2 different conditions:
1. regular vote submission. That's the common case.
2. submission of the last vote. That happens only once and leads to a
heavy finalization stage.
There are 2 different types of finalization (one for onboarding, one for
upgrading) and there are two outcomes: accepted and rejected. Those 4
are similar but I decided to cover them all and assign the maximum of
all 4. This is to avoid a situation when one of those paths becomes more
heavier than others and opens up an attack venue.
The regular vote submission weight is drastically different from the
submission last vote weight. That's why in case during runtime
finalization was not executed the weight consumed value will be lowered
down to the regular vote submission.
The finalization weight is proportional to the number of "causes", i.e.
the events that caused the PVF pre-checking vote in the first place, and
here we assume that the maximum number of causes is 100.
Theoretically, there is nothing that prevents an adversary to
register/upgrade to more than 100 parachains. In that case, the consumed
weight will be lower than the actual time consumed by the finalization
process. That can enable a DoS vector.
However, practically, it is not very possible. Right now it is very
expensive to call `schedule_para_initialize` because it requires a very
large lock up of funds. Moreover, finalizing a vote with 100 causes
leads to around 31ms time spent. Finalizing more will require more time.
However, finalizing with 200 causes will cause ≈62ms delay. This is not
that bad since even though we had a full block and the adversary tried
to finalize 200 causes it won't be able to even exceed the operational
extrinsic boundary of 250ms and even if so it won't make big difference.
That said, this should be addressed later on, esp. when we enable
parathreads, which will make creating causes easier. One of potential
solutions will be shifting the logic of finalization into
`on_initialize`/`on_finalize`. Another is to create a maximum number of
causes and then reject upgrades or onboardings if that was reached.
* cargo run --quiet --profile=production --features=runtime-benchmarks -- benchmark --chain=polkadot-dev --steps=50 --repeat=20 --pallet=runtime_parachains::paras --extrinsic=* --execution=wasm --wasm-execution=compiled --heap-pages=4096 --header=./file_header.txt --output=./runtime/polkadot/src/weights/runtime_parachains_paras.rs
* cargo run --quiet --profile=production --features=runtime-benchmarks -- benchmark --chain=kusama-dev --steps=50 --repeat=20 --pallet=runtime_parachains::paras --extrinsic=* --execution=wasm --wasm-execution=compiled --heap-pages=4096 --header=./file_header.txt --output=./runtime/kusama/src/weights/runtime_parachains_paras.rs
* cargo run --quiet --profile=production --features=runtime-benchmarks -- benchmark --chain=westend-dev --steps=50 --repeat=20 --pallet=runtime_parachains::paras --extrinsic=* --execution=wasm --wasm-execution=compiled --heap-pages=4096 --header=./file_header.txt --output=./runtime/westend/src/weights/runtime_parachains_paras.rs
* cargo run --quiet --profile=production --features runtime-benchmarks -- benchmark --chain=rococo-dev --steps=50 --repeat=20 --pallet=runtime_parachains::paras --extrinsic=* --execution=wasm --wasm-execution=compiled --heap-pages=4096 --header=./file_header.txt --output=./runtime/rococo/src/weights/runtime_parachains_paras.rs
* Fix import error
Co-authored-by: Parity Bot <admin@parity.io>
Co-authored-by: Robert Klotzner <robert.klotzner@gmx.at>
Co-authored-by: Lldenaurois <Ljdenaurois@gmail.com>
* paras: add governance control dispatchables
Adds a couple of functions for governance control for the paras module
in the anticipation of PVF pre-checking enabling.
Specifically, this commit adds a function for pre-registering a PVF that
governance trusts enough. This function will come in handy in case there
is a parachain that does not follow the GoAhead signal. That is, does
not include https://github.com/paritytech/cumulus/pull/517.
This may be not an exhaustive list of the functions that may come in
handy. Any suggestions to add more are welcome.
* cargo run --quiet --release --features=runtime-benchmarks -- benchmark --chain=kusama-dev --steps=50 --repeat=20 --pallet=runtime_parachains::paras --extrinsic=* --execution=wasm --wasm-execution=compiled --heap-pages=4096 --header=./file_header.txt --output=./runtime/kusama/src/weights/runtime_parachains_paras.rs
* cargo run --quiet --release --features=runtime-benchmarks -- benchmark --chain=polkadot-dev --steps=50 --repeat=20 --pallet=runtime_parachains::paras --extrinsic=* --execution=wasm --wasm-execution=compiled --heap-pages=4096 --header=./file_header.txt --output=./runtime/polkadot/src/weights/runtime_parachains_paras.rs
* cargo run --quiet --release --features=runtime-benchmarks -- benchmark --chain=westend-dev --steps=50 --repeat=20 --pallet=runtime_parachains::paras --extrinsic=* --execution=wasm --wasm-execution=compiled --heap-pages=4096 --header=./file_header.txt --output=./runtime/westend/src/weights/runtime_parachains_paras.rs
* cargo run --quiet --release --features runtime-benchmarks -- benchmark --chain=rococo-dev --steps=50 --repeat=20 --pallet=runtime_parachains::paras --extrinsic=* --execution=wasm --wasm-execution=compiled --heap-pages=4096 --header=./file_header.txt --output=./runtime/rococo/src/weights/runtime_parachains_paras.rs
Co-authored-by: Parity Bot <admin@parity.io>
* pvf-precheck: Integrate PVF pre-checking into paras module
Closes#4009
This is the most of the runtime-side change needed for #3211.
Here is how it works.
The PVF pre-checking can be triggered either by an upgrade or by
onboarding (i.e. calling `schedule_para_initialize`). The PVF
pre-checking process is identified by the PVF code hash that is being
voted on. If there is already PVF pre-checking process running, then no
new PVF pre-checking process will be started. Instead, we just subscribe
to the existing one.
If there is no PVF pre-checking process running but the PVF code hash
was already saved in the storage, that necessarily means (I invite the
reviewers to double-check this invariant) that the PVF already passed
pre-checking. This is equivalent to instant approving of the PVF.
The pre-checking process can be concluded either by obtaining a
supermajority or if it expires.
Each validator checks the list of PVFs available for voting. The vote is
binary, i.e. accept or reject a given PVF. As soon as the supermajority
of votes are collected for one of the sides of the vote, the voting is
concluded in that direction and the effects of the voting are enacted.
Only validators from the active set can participate in the vote. The set
of active validators can change each session. That's why we reset the
votes each session. A voting that observed a certain number of sessions
will be rejected.
The effects of the PVF accepting depend on the operations requested it:
1. All onboardings subscribed to the approved PVF pre-checking process will
get scheduled and after passing 2 session boundaries they will be onboarded.
2. All upgrades subscribed to the approved PVF pre-checking process will
get scheduled very similarly to the existing process. Upgrades with
pre-checking are really the same process that is just delayed by the
time required for pre-checking voting. In case of instant approval the
mechanism is exactly the same. This is important from parachains
compatibility standpoint since following the delayed upgrade requires
the parachain to implement
https://github.com/paritytech/cumulus/pull/517.
In case, PVF pre-checking process was concluded with rejection, then all
the requesting operations get cancelled. For onboarding it means it gets
without movement: the lifecycle of such parachain is terminated on the
`Onboarding` state and after rejection the lifecycle is none. That in
turn means that the caller can attempt registering the parachain once
more. For upgrading it means that the upgrade process is aborted: that
flashes go-ahead signal with `Abort` flag.
Rejection leads to removing the allegedly bad validation code from the
chain storage. Among other things, this implies that the operation can
be re-requested. That allows for retrying an operation in case there was
some bug. At the same time it does not look as a DoS vector due to the
caching performed by the nodes.
PVF pre-checking can be enabled and disabled. Initially, according to
the changes in #4420, this mechanism is disabled. Triggering the PVF
pre-checking when it is disabled just means that we insta approve the
requesting operation. This should lead to the behavior being unchanged.
Follow-ups:
- expose runtime APIs
* cargo run --quiet --release --features=runtime-benchmarks -- benchmark --chain=polkadot-dev --steps=50 --repeat=20 --pallet=runtime_parachains::paras --extrinsic=* --execution=wasm --wasm-execution=compiled --heap-pages=4096 --header=./file_header.txt --output=./runtime/polkadot/src/weights/runtime_parachains_paras.rs
* cargo run --quiet --release --features=runtime-benchmarks -- benchmark --chain=westend-dev --steps=50 --repeat=20 --pallet=runtime_parachains::paras --extrinsic=* --execution=wasm --wasm-execution=compiled --heap-pages=4096 --header=./file_header.txt --output=./runtime/westend/src/weights/runtime_parachains_paras.rs
* cargo run --quiet --release --features=runtime-benchmarks -- benchmark --chain=kusama-dev --steps=50 --repeat=20 --pallet=runtime_parachains::paras --extrinsic=* --execution=wasm --wasm-execution=compiled --heap-pages=4096 --header=./file_header.txt --output=./runtime/kusama/src/weights/runtime_parachains_paras.rs
* cargo run --quiet --release --features runtime-benchmarks -- benchmark --chain=rococo-dev --steps=50 --repeat=20 --pallet=runtime_parachains::paras --extrinsic=* --execution=wasm --wasm-execution=compiled --heap-pages=4096 --header=./file_header.txt --output=./runtime/rococo/src/weights/runtime_parachains_paras.rs
* Review fixes
Co-authored-by: Parity Bot <admin@parity.io>
Mara Robin B