s0me0ne-unkn0wn
c26cf3f6f2
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
PVF Host
This is the PVF host, responsible for responding to requests from Candidate Validation and spawning worker tasks to fulfill those requests.
See also:
- for more information: the Implementer's Guide
- for an explanation of terminology: the Glossary
Running basic tests
Running cargo test in the pvf/ directory will run unit and integration
tests.
Note: some tests run only under Linux, x86-64, and/or with the
ci-only-tests feature enabled.
See the general Testing instructions for more information on running tests and observing logs.
Running a test-network with zombienet
Since this crate is consensus-critical, for major changes it is highly recommended to run a test-network. See the "Behavior tests" section of the Testing docs for full instructions.
To run the PVF-specific zombienet test:
RUST_LOG=parachain::pvf=trace zombienet --provider=native spawn zombienet_tests/functional/0001-parachains-pvf.toml
Testing on Linux
Some of the PVF functionality, especially related to security, is Linux-only, and some is x86-64-only. If you touch anything security-related, make sure to test on Linux x86-64! If you're on a Mac, you can either run a VM or you can hire a VPS and use the open-source tool EternalTerminal to connect to it.1
-
Unlike ssh, ET preserves your session across disconnects, and unlike another popular persistent shell, mosh, it allows scrollback. ↩︎