Community Update 189


Sprint 96 in progress

Main Focus is to prepare the block merge Hard fork (hf2), specifically (a) merging REV balances directly - in process (b) leaderless block merge - work ongoing (c) a lot of testing + bug fixing and (d) performance improvements. Other work items include resolving any identified bugs,  hardening the network.  Current PR list is at .  

Block merge Hard Fork (hf2)

  1. Nutzipper is able to reconcile his leaderless state merge changes (based on a fringe/boundary of previous last finalized states) with the code base and is able to compile RNode running locally. He is now testing this logically to identify any bugs. In particular, he's working on some changes to finalization and Casper so that finalization can move forward in all cases.
  2. Tomislav will demo today the merging of REV balances directly. . He has to make some more changes to complete REV vault merging.
  3. We are getting ever closer to the HF2 release for testing, which will be possible when the above two efforts are complete and we merge that into the code base.
  4. Additional work to be done: refactor any necessary tests including Casper tests, run and troubleshoot any identified issues.
  5. We still have not identified the reason for the sooner than expected slow down in linear scaling. Will continues to work on this. Based on analysis so far, increase in tuple space size, disk i/o, memory or cpu do not seem to be the issues. Current suspect is JVM or related factors. We have not seen anything in the code slowing things down. Will is now further simplifying the test scenario to just run produces and consumes (without any refunds, pre-charges etc.) and observe the behavior, so we can learn from bottom up where the machinery is slowing things down. 
  6. Denis is getting his PR ready for RadixTree implementation of History (it will initially go on Tomislav's branch). He demonstrated 2x improvement on inserts. He will be updating the PR with performance improvement results for read, delete, insert operations.  Full impact of his improvements will be known only after we merge this into the main code base, which has more steps to go through.
  7. Status of various Block merge tasks is at

Release Plan for the rest of the year and beyond - for reference

Currently planned near term releases are

  1. Block merge release hard fork 2 plus any configuration changes that do not need extensive work - Leaderful and Leaderless block merge
  2. Configuration changes release,
  3. Performance improvements releases (one or more),
  4. Hard Fork 3 with PoS changes and other items,
  5. External validators process validation with trusted community validators (aka Friends & Family) on the test net
  6. Friends & Family validation on the main net
  7. External validators among extended ecosystem (e.g. exchanges, if they're willing)
  8. External validators in the wild.

Explanation of the different Hard Forks (for reference)

Proceeding further with block merge requires changes to the per validator vault to make it a per deploy vault/purse etc. We are currently finalizing the design for this. Actual code and test will take some time. We are potentially looking at this scenario:
1. First hard fork for balances and removing the slashed validator
2. Second hard fork for block merge - This is the fastest way to get block merge on the main net without holding it until the third hard fork. This includes REV balance merging (aka per deploy vault), attestation messages and the Tree depth being increased to 4.
3. Third hard fork with all other changes.  Third hard fork includes implementation of a lot of changes including the PoS contract changes, Soft fork process etc.  Design for soft fork process is complete and is being reviewed by the team.

(Hard Fork) TEST NET 2 ADVISORY: (for reference)

To test the version of block merge with data changes that need a hard fork, we are creating a separate feature branch and a TEST NET 2 as the testbed for this feature branch. This content will be left here until we are close to Hard Fork 2 implementation on the main net. TestNet 2 is now available for the community to test their contracts on.

  1. There will be no guarantees of data storage format compatibility on Test Net 2, as the data storage format changes are incrementally implemented. The anticipated changes are mostly storage level format changes visible only to node operators. We encourage the community to start using Test Net 2 in addition to the current test net, so that we can quickly identify and resolve any issues with the upcoming hard forks. All new development should be targeted to TEST NET 2 and all current code MUST BE tested against TEST NET 2 to ensure future compatibility. 

On all the hard forks on the main net, we will be starting from an empty state, with REV balances only. On Test Net 2, this 'loosing the state' will be repeated multiple times.

Tech-Governance meetings on Fridays 9:30 AM Eastern, 6:30 Am Pacific 

Mercury requirements and acceptance criteria

Details on the acceptance criteria: Mercury acceptance criteria

Please see the documentation at

Developer website