Alin Dima
62b78a1615
https://github.com/paritytech/polkadot-sdk/issues/3130 builds on top of https://github.com/paritytech/polkadot-sdk/pull/3160 Processes the availability cores and builds a record of how many candidates it should request from prospective-parachains and their predecessors. Tries to supply as many candidates as the runtime can back. Note that the runtime changes to back multiple candidates per para are not yet done, but this paves the way for it. The following backing/inclusion policy is assumed: 1. the runtime will never back candidates of the same para which don't form a chain with the already backed candidates. Even if the others are still pending availability. We're optimistic that they won't time out and we don't want to back parachain forks (as the complexity would be huge). 2. if a candidate is timed out of the core before being included, all of its successors occupying a core will be evicted. 3. only the candidates which are made available and form a chain starting from the on-chain para head may be included/enacted and cleared from the cores. In other words, if para head is at A and the cores are occupied by B->C->D, and B and D are made available, only B will be included and its core cleared. C and D will remain on the cores awaiting for C to be made available or timed out. As point (2) above already says, if C is timed out, D will also be dropped. 4. The runtime will deduplicate candidates which form a cycle. For example if the provisioner supplies candidates A->B->A, the runtime will only back A (as the state output will be the same) Note that if a candidate is timed out, we don't guarantee that in the next relay chain block the block author will be able to fill all of the timed out cores of the para. That increases complexity by a lot. Instead, the provisioner will supply N candidates where N is the number of candidates timed out, but doesn't include their successors which will be also deleted by the runtime. This'll be backfilled in the next relay chain block. Adjacent changes: - Also fixes: https://github.com/paritytech/polkadot-sdk/issues/3141 - For non prospective-parachains, don't supply multiple candidates per para (we can't have elastic scaling without prospective parachains enabled). paras_inherent should already sanitise this input but it's more efficient this way. Note: all of these changes are backwards-compatible with the non-elastic-scaling scenario (one core per para).
NOTE: We have recently made significant changes to our repository structure. In order to streamline our development process and foster better contributions, we have merged three separate repositories Cumulus, Substrate and Polkadot into this repository. Read more about the changes here.
Polkadot SDK
The Polkadot SDK repository provides all the resources needed to start building on the Polkadot network, a multi-chain blockchain platform that enables different blockchains to interoperate and share information in a secure and scalable way. The Polkadot SDK comprises three main pieces of software:
Polkadot
Implementation of a node for the https://polkadot.network in Rust, using the Substrate framework. This directory
currently contains runtimes for the Westend and Rococo test networks. Polkadot, Kusama and their system chain runtimes
are located in the runtimes repository maintained by
the Polkadot Technical Fellowship.
Substrate
Substrate is the primary blockchain SDK used by developers to create the parachains that make up the Polkadot network. Additionally, it allows for the development of self-sovereign blockchains that operate completely independently of Polkadot.
Cumulus
Cumulus is a set of tools for writing Substrate-based Polkadot parachains.
Releases
Note
Our release process is still Work-In-Progress and may not yet reflect the aspired outline here.
The Polkadot-SDK has two release channels: stable and nightly. Production software is advised to only use stable.
nightly is meant for tinkerers to try out the latest features. The detailed release process is described in
RELEASE.md.
Stable
stable releases have a support duration of three months. In this period, the release will not have any breaking
changes. It will receive bug fixes, security fixes, performance fixes and new non-breaking features on a two week
cadence.
Nightly
nightly releases are released every night from the master branch, potentially with breaking changes. They have
pre-release version numbers in the format major.0.0-nightlyYYMMDD.
Upstream Dependencies
Below are the primary upstream dependencies utilized in this project:
Security
The security policy and procedures can be found in docs/contributor/SECURITY.md.
Contributing & Code of Conduct
Ensure you follow our contribution guidelines. In every interaction and contribution, this project adheres to the Contributor Covenant Code of Conduct.
Additional Resources
- For monitoring upcoming changes and current proposals related to the technical implementation of the Polkadot network,
visit the
Requests for Comment (RFC)repository. While it's maintained by the Polkadot Fellowship, the RFC process welcomes contributions from everyone.