Currently, PVFs are re-prepared if any execution environment parameter
changes. As we've recently seen on Kusama and Polkadot, that may lead to
a severe finality lag because every validator has to re-prepare every
PVF. That cannot be avoided altogether; however, we could cease
re-preparing PVFs when a change in the execution environment can't lead
to a change in the artifact itself. For example, it's clear that
changing the execution timeout cannot affect the artifact.

In this PR, I'm introducing a separate hash for the subset of execution
environment parameters that changes only if a preparation-related
parameter changes. It introduces some minor code duplication, but
without that, the scope of changes would be much bigger.

TODO:
- [x] Add a test to ensure the artifact is not re-prepared if
non-preparation-related parameter is changed
- [x] Add a test to ensure the artifact is re-prepared if a
preparation-related parameter is changed
- [x] Add comments, warnings, and, possibly, a test to ensure a new
parameter ever added to the executor environment parameters will be
evaluated by the author of changes with respect to its artifact
preparation impact and added to the new hash preimage if needed.

Closes #4132

Part of https://github.com/paritytech/polkadot-sdk/issues/4126

 we want
to safely increase the execute_workers_max_num gradually from chain to
chain and assess if there are any negative impacts.

This PR performs the necessary plumbing to be able to increase it based
on the chain id, it increase the number of execution workers from 2 to 4
on test network but lives kusama and polkadot unchanged until we gather
more data.

---------

Signed-off-by: Alexandru Gheorghe <[email protected]>

Add a metric to be able to understand the time jobs are waiting in the
execution queue waiting for an available worker.
https://github.com/paritytech/polkadot-sdk/issues/4126



Signed-off-by: Alexandru Gheorghe <[email protected]>

follow up of https://github.com/paritytech/polkadot-sdk/pull/2604
closes https://github.com/paritytech/polkadot-sdk/pull/2604

- [x] take relevant changes from Marcin's PR 
- [x] extract common duplicate code for workers (low-hanging fruits)

~Some unpassed ci problems are more general and should be fixed in
master (see https://github.com/paritytech/polkadot-sdk/pull/4074)~



Proposed labels: **T0-node**, **R0-silent**, **I4-refactor**

-----

kusama address: FZXVQLqLbFV2otNXs6BMnNch54CFJ1idpWwjMb3Z8fTLQC6

---------

Co-authored-by: s0me0ne-unkn0wn <[email protected]>

Related to https://github.com/paritytech/polkadot-sdk/issues/4126


discussion

Currently all preparations have same priority and this is not ideal in
all cases. This change should improve the finality time in the context
of on-demand parachains and when `ExecutorParams` are updated on-chain
and a rebuild of all artifacts is required. The desired effect is to
speed up approval and dispute PVF executions which require preparation
and delay backing executions which require preparation.

---------

Signed-off-by: Andrei Sandu <[email protected]>

**Update:** Pushed additional changes based on the review comments.

**This pull request fixes various spelling mistakes in this
repository.**

Most of the changes are contained in the first **3** commits:

- `Fix spelling mistakes in comments and docs`

- `Fix spelling mistakes in test names`

- `Fix spelling mistakes in error messages, panic messages, logs and
tracing`

Other source code spelling mistakes are separated into individual
commits for easier reviewing:

- `Fix the spelling of 'authority'`

- `Fix the spelling of 'REASONABLE_HEADERS_IN_JUSTIFICATION_ANCESTRY'`

- `Fix the spelling of 'prev_enqueud_messages'`

- `Fix the spelling of 'endpoint'`

- `Fix the spelling of 'children'`

- `Fix the spelling of 'PenpalSiblingSovereignAccount'`

- `Fix the spelling of 'PenpalSudoAccount'`

- `Fix the spelling of 'insufficient'`

- `Fix the spelling of 'PalletXcmExtrinsicsBenchmark'`

- `Fix the spelling of 'subtracted'`

- `Fix the spelling of 'CandidatePendingAvailability'`

- `Fix the spelling of 'exclusive'`

- `Fix the spelling of 'until'`

- `Fix the spelling of 'discriminator'`

- `Fix the spelling of 'nonexistent'`

- `Fix the spelling of 'subsystem'`

- `Fix the spelling of 'indices'`

- `Fix the spelling of 'committed'`

- `Fix the spelling of 'topology'`

- `Fix the spelling of 'response'`

- `Fix the spelling of 'beneficiary'`

- `Fix the spelling of 'formatted'`

- `Fix the spelling of 'UNKNOWN_PROOF_REQUEST'`

- `Fix the spelling of 'succeeded'`

- `Fix the spelling of 'reopened'`

- `Fix the spelling of 'proposer'`

- `Fix the spelling of 'InstantiationNonce'`

- `Fix the spelling of 'depositor'`

- `Fix the spelling of 'expiration'`

- `Fix the spelling of 'phantom'`

- `Fix the spelling of 'AggregatedKeyValue'`

- `Fix the spelling of 'randomness'`

- `Fix the spelling of 'defendant'`

- `Fix the spelling of 'AquaticMammal'`

- `Fix the spelling of 'transactions'`

- `Fix the spelling of 'PassingTracingSubscriber'`

- `Fix the spelling of 'TxSignaturePayload'`

- `Fix the spelling of 'versioning'`

- `Fix the spelling of 'descendant'`

- `Fix the spelling of 'overridden'`

- `Fix the spelling of 'network'`

Let me know if this structure is adequate.

**Note:** The usage of the words `Merkle`, `Merkelize`, `Merklization`,
`Merkelization`, `Merkleization`, is somewhat inconsistent but I left it
as it is.

~~**Note:** In some places the term `Receival` is used to refer to
message reception, IMO `Reception` is the correct word here, but I left
it as it is.~~

~~**Note:** In some places the term `Overlayed` is used instead of the
more acceptable version `Overlaid` but I also left it as it is.~~

~~**Note:** In some places the term `Applyable` is used instead of the
correct version `Applicable` but I also left it as it is.~~

**Note:** Some usage of British vs American english e.g. `judgement` vs
`judgment`, `initialise` vs `initialize`, `optimise` vs `optimize` etc.
are both present in different places, but I suppose that's
understandable given the number of contributors.

~~**Note:** There is a spelling mistake in `.github/CODEOWNERS` but it
triggers errors in CI when I make changes to it, so I left it as it
is.~~

resolve https://github.com/paritytech/polkadot-sdk/issues/3139

- [x] use a distinguishable error for `execute_artifact`
- [x] remove artifact in case of a `RuntimeConstruction` error during
the execution
- [x] augment the `validate_candidate_with_retry` of `ValidationBackend`
with the case of retriable `RuntimeConstruction` error during the
execution
- [x] update the book
(https://paritytech.github.io/polkadot-sdk/book/node/utility/pvf-host-and-workers.html#retrying-execution-requests

)
- [x] add a test
- [x] run zombienet tests

---------

Co-authored-by: s0me0ne-unkn0wn <[email protected]>

resolve https://github.com/paritytech/polkadot-sdk/issues/2321



- [x] refactor `security` module into a conditionally compiled
- [x] rename `amd64` into x86-64 for consistency with conditional
compilation guards and remove reference to a particular vendor
- [x] run unit tests and zombienet

---------

Co-authored-by: s0me0ne-unkn0wn <[email protected]>

This PR aims to channel the backpressure of the PVF host's preparation
and execution queues to the candidate validation subsystem consumers.

Related: #708

@mrcnski Done the change on the prepare worker, once the prepare worker
part is good I'll do the same for the execute worker.

This is based on
https://github.com/koute/polkavm/blob/11beebd06276ce9b84f335350138479e714f6caf/crates/polkavm/src/sandbox/linux.rs#L711

.

## TODO

- [x] Add a check for this capability at startup
- [x] Add prdoc mentioning the new Secure Validator Mode (optional)
requirement.

## Related

Closes #2162

---------

Co-authored-by: Marcin S <[email protected]>

resolve #2157 

- [x] fix broken doc links
- [x] fix codec macro typo
https://github.com/paritytech/polkadot-sdk/blob/master/polkadot/node/core/pvf/common/src/error.rs#L81
(see the comment below)
- [x] refactor `ValidationError`, `PrepareError` and related error types
to use `thiserror` crate

## `codec` issue

`codec` macro was mistakenly applied two times to `Kernel` error (so it
was encoded with 10 instead of 11 and the same as `JobDied`). The PR
changes it to 11 because

- it was an initial goal of the code author
- Kernel is less frequent than JobDied so in case of existing error
encoding it is more probable to have 10 as JobDied than Kernel

See https://github.com/paritytech/parity-scale-codec/issues/555



----
polkadot address: 13zCyRG2a1W2ih5SioL8byqmQ6mc8vkgFwQgVzJSdRUUmp46

---------

Co-authored-by: s0me0ne-unkn0wn <[email protected]>

Considering the complexity of
https://github.com/paritytech/polkadot-sdk/pull/2871 and the discussion
therein, as well as the further complexity introduced by the hardening
in https://github.com/paritytech/polkadot-sdk/pull/2742, as well as the
eventual replacement of wasmtime by PolkaVM, it seems best to remove
this persistence as it is creating more problems than it solves.

## Related

Closes https://github.com/paritytech/polkadot-sdk/issues/2863

Fixes a potential memory leak.

`PR_SET_PDEATHSIG` is used to terminate children when the parent dies.
Note that this is subject to a race. There seems to be a raceless
alternative [here](https://stackoverflow.com/a/42498370/6085242), but
the concern is small enough that a bit more complexity doesn't seem
worth it. Left a bit more info in the code comment.

Co-authored-by: Alexandru Vasile <[email protected]>

Co-authored-by: Javier Viola <[email protected]>

closes #2194 

cc @mrcnski



---------

Co-authored-by: Bastian Köcher <[email protected]>

Co-authored-by: Marcin S <[email protected]>

Co-authored-by: Marcin S <[email protected]>

Co-authored-by: Bastian Köcher <[email protected]>

closes #695

Could potentially be helpful to preserving caches when applicable, as
discussed in #685

kusama address: FvpsvV1GQAAbwqX6oyRjemgdKV11QU5bXsMg9xsonD1FLGK

closes #622 

Pros:
* simpler interface, just functions:
`create_runtime_from_artifact_bytes()` and `execute_artifact()`

Cons:
* extra overhead of constructing executor semantics each time

I could make it a combination of
* `create_runtime_config(params)` (such that we could clone the
constructed semantics)
* `create_runtime(blob, config)`
* `execute_artifact(blob, config, params)`

Not sure if it's worth it though.

---------

Co-authored-by: Bastian Köcher <[email protected]>

# Description

In a couple of cases, there were links pointing to the w3f github pages
domain. In other instances, there were links pointing to the old
polkadot repo's github pages. Both of these are now pointing to the
relevant links in
https://paritytech.github.io/polkadot-sdk/book/index.html.

These changes were made specifically because the w3f github pages
returns a 404, and while fixing the links, the old polkadot repo links
were touched up as well even if they do redirect properly.

This shouldn't affect anything as these are documentation link changes
only.

Closes #583

After the separation of PVF worker binaries, dedicated puppet workers
are not needed for tests anymore. The production workers can be used
instead, avoiding some code duplication and decreasing complexity.

The changes also make it possible to further refactor the code to
isolate workers completely.

* Rename `polkadot-parachain` to `polkadot-parachain-primitives`

While doing this it also fixes some last `rustdoc` issues and fixes
another Cargo warning related to `pallet-paged-list`.

* Fix compilation

* ".git/.scripts/commands/fmt/fmt.sh"

* Fix XCM docs

---------

Co-authored-by: command-bot <>

* Use same rustfmt.toml as Substrate

Signed-off-by: Oliver Tale-Yazdi <[email protected]>

* format format file

Signed-off-by: Oliver Tale-Yazdi <[email protected]>

* Format with new config

Signed-off-by: Oliver Tale-Yazdi <[email protected]>

* Add Substrate Clippy config

Signed-off-by: Oliver Tale-Yazdi <[email protected]>

* Print Clippy version in CI

Otherwise its difficult to reproduce locally.

Signed-off-by: Oliver Tale-Yazdi <[email protected]>

* Make fmt happy

Signed-off-by: Oliver Tale-Yazdi <[email protected]>

* Update node/core/pvf/src/error.rs

Co-authored-by: Tsvetomir Dimitrov <[email protected]>

* Update node/core/pvf/src/error.rs

Co-authored-by: Tsvetomir Dimitrov <[email protected]>

---------

Signed-off-by: Oliver Tale-Yazdi <[email protected]>
Co-authored-by: Tsvetomir Dimitrov <[email protected]>

* pvf: use test-utils feature to export test only

* adding comment to test-utils feature

* make prepare-worker and execute-worker as optional dependencies and add comments to test-utils

* remove doc hidden from pvf testing

* add prepare worker and execute worker entrypoints to test-utils feature

* pvf: add sp_tracing as optional dependency of test-utils

* add test-utils for polkadot and malus

* add test-utils feature to prepare and execute workers script

* remove required features from prepare and executing

* Try to trigger CI again to fix broken jobs

---------

Co-authored-by: Marcin S <[email protected]>

* [WIP] PVF: Split out worker binaries

* Address compilation problems and re-design a bit

* Reorganize once more, fix tests

* Reformat with new nightly to make `cargo fmt` test happy

* Address `clippy` warnings

* Add temporary trace to debug zombienet tests

* Fix zombienet node upgrade test

* Fix malus and its CI

* Fix building worker binaries with malus

* More fixes for malus

* Remove unneeded cli subcommands

* Support placing auxiliary binaries to `/usr/libexec`

* Fix spelling

* Spelling

Co-authored-by: Marcin S. <[email protected]>

* Implement review comments (mostly nits)

* Fix worker node version flag

* Rework getting the worker paths

* Address a couple of review comments

* Minor restructuring

* Fix CI error

* Add tests for worker binaries detection

* Improve tests; try to fix CI

* Move workers module into separate file

* Try to fix failing test and workers not printing latest version

- Tests were not finding the worker binaries
- Workers were not being rebuilt when the version changed
- Made some errors easier to read

* Make a bunch of fixes

* Rebuild nodes on version change

* Fix more issues

* Fix tests

* Pass node version from node into dependencies to avoid recompiles

- [X] get version in CLI
- [X] pass it in to service
- [X] pass version along to PVF
- [X] remove rerun from service
- [X] add rerun to CLI

- [X] don’t rerun pvf/worker’s (these should be built by nodes which have rerun enabled)

* Some more improvements for smoother tests

- [X] Fix tests
- [X] Make puppet workers pass None for version and remove rerun
- [X] Make test collators self-contained

* Add back rerun to PVF workers

* Move worker binaries into files in cli crate

As a final optimization I've separated out each worker binary from its own crate
into the CLI crate. Before, the worker bin shared a crate with the worker lib,
so when the binaries got recompiled so did the libs and everything transitively
depending on the libs. This commit fixes this regression that was causing
recompiles after every commit.

* Fix bug (was passing worker version for node version)

* Move workers out of cli into root src/bin/ dir

- [X] Pass in node version from top-level (polkadot)
- [X] Add build.rs with rerun-git-head to root dir

* Add some sanity checks for workers to dockerfiles

* Update malus

  + [X] Make it self-contained
  + [X] Undo multiple binary changes

* Try to fix clippy errors

* Address `cargo run` issue

- [X] Add default-run for polkadot
- [X] Add note about installation to error

* Update readme (installation instructions)

* Allow disabling external workers for local/testing setups

  + [X] cli flag to enable single-binary mode
  + [X] Add message to error

* Revert unnecessary Cargo.lock changes

* Remove unnecessary build scripts from collators

* Add back missing malus commands (should fix failing ZN job)

* Some minor fixes

* Update Cargo.lock

* Fix some build errors

* Undo self-contained binaries; cli flag to disable version check

  + [X] Remove --dont-run-external-workers
  + [X] Add --disable-worker-version-check
  + [X] Remove PVF subcommands
  + [X] Redo malus changes

* Try to fix failing job and add some docs for local tests

---------

Co-authored-by: Dmitry Sinyavin <[email protected]>
Co-authored-by: s0me0ne-unkn0wn <[email protected]>
Co-authored-by: parity-processbot <>