Axon Development Updates 09/06/2023

[KaoImin]

Somewhere in the earth

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Hey, we hope you've been keeping an eye on Axon's progress. We'd like to bring to your attention that there hasn't been a new Axon release since July 13th. During this time, our dedicated Axon team has been hard at work on the highly anticipated Axon 0.2.0-beta version.

While preparing for this release, we encountered some bugs that have the potential to introduce breaking changes. To address this, we embarked on a journey of data migration. However, it hasn't been a completely smooth process. After extensive discussions, we decided to implement a hardfork mechanism to ensure a seamless transition. In addition to resolving these challenges, we're excited to share that we've been working on numerous impactful features and code refactors. We're pleased to announce that these efforts are nearing completion and let me introduce the mainly changes:

Hardfork Mechanism

The introduction of the hardfork mechanism marks a significant milestone in our development. Starting from version 0.2.0-beta, all breaking changes will be seamlessly managed through this mechanism. This proposal has been under discussion #1317 for some time, and you can find the related PR in the following link:

• refactor: change config to single struct #1328
• feat: add hardfork storage to metadata contract #1380
• feat: hardfork proposal feature #1404

CLI Refactor

There is a big change in Axon CLI. Firstly, we've split the start command into two separate commands: init and run, as detailed in #1386. This change enhances developers' ability to customize their chains effortlessly. Additionally, we've made adjustments to the genesis process. It now operates with a spec that includes transactions within the genesis, a modification outlined in #1332. The remaining portion of the genesis will be calculated during the initial process, streamlining the setup. Notably, we've also refactored the CLI code using the 'derive' macro, as outlined in #1326. These changes collectively contribute to an improved and more efficient CLI experience.

Merge RocksDB Instances

Previously, Axon maintained four RocksDB instances within the same process. This setup, however, posed some challenges. Specifically, some instances were infrequently accessed, causing memtable unable to be flushed for a long time. Furthermore, having different storage paths increased the risk of data tampering. To address these concerns and enhance system stability, PR #1338 has been introduced. This PR successfully resolves these issues by implementing read-write separation. This not only reduces the likelihood of introducing bugs during development but also optimizes memory usage.

Other Breaking Changes

0.2.0-beta version has some breaking changes:

• Make the calculation of receipts_root same as EIP-2718 fix(consensus): correct receipts root #1270
• The addresses in config file must follow EIP-55 standard feat: import addresses with EIP-55 #1340
• Add version field and remove some useless fields of Header feat!: add version field to block header and proposal #1319 refactor!: remove useless fields in BlockHeader #1339
• Change the memory layout and rlp codec of Hex refactor: change the inner type of Hex #1371 refactor!: change the rlp codec of Hex #1382 fix: Hex serde deserialize #1396

Other Bugfixes and Code Refactors

During this time we make many code refactors:

• Use thread local instead of global variable refactor(executor): thread local instead of global variable #1280
• Fix modexp precompile contract may overflow and reduce memory cost fix(precompile): fix overflow sub #1299 perf: reduce mem cost on modexp #1300
• Get client version from crate version and git commit ID refactor: get client version from crate and git #1309
• Make chain id immutable refactor(network): immutable chain id #1351
• Slightly improve security for secret keys refactor: slightly improve security for secret keys #1367

Let's anticipate the release of Axon 0.2.0-beta!