Skip to content

dcrd v1.4.0-rc3

Pre-release
Pre-release
Compare
Choose a tag to compare
@davecgh davecgh released this 28 Jan 19:23
· 2869 commits to master since this release
release-v1.4.0-rc3
This tag was signed with the committer’s verified signature.
davecgh Dave Collins
GPG key ID: B8904D9D9C93D1F2
Learn about vigilant mode.
e3e8c47
This commit was signed with the committer’s verified signature.
davecgh Dave Collins
GPG key ID: B8904D9D9C93D1F2
Learn about vigilant mode.

This release of dcrd introduces a new consensus vote agenda which allows the
stakeholders to decide whether or not to activate changes needed to modify the
sequence lock handling which is required for providing full support for the
Lightning Network. For those unfamiliar with the voting process in Decred, this
means that all code in order to make the necessary changes is already included
in this release, however its enforcement will remain dormant until the
stakeholders vote to activate it.

It also contains smart fee estimation, performance enhancements for block relay
and processing, a major internal restructuring of how unspent transaction
outputs are handled, support for whitelisting inbound peers to ensure service
for your own SPV (Simplified Payment Verification) wallets, various updates to
the RPC server such as a new method to query the state of the chain and more
easily supporting external RPC connections over TLS, infrastructure
improvements, and other quality assurance changes.

The following Decred Change Proposals (DCP) describes the proposed changes in detail:

It is important for everyone to upgrade their software to this latest release
even if you don't intend to vote in favor of the agenda.

Downgrade Warning

The database format in v1.4.0 is not compatible with previous versions of the
software. This only affects downgrades as users upgrading from previous
versions will see a lengthy one time database migration.

Once this migration has been completed, it will no longer be possible to
downgrade to a previous version of the software without having to delete the
database and redownload the chain.

Notable Changes

Fix Lightning Network Sequence Locks Vote

In order to fully support the Lightning Network, the current sequence lock
consensus rules need to be modified. A new vote with the id fixlnseqlocks is
now available as of this release. After upgrading, stakeholders may set their
preferences through their wallet or Voting Service Provider's (VSP) website.

Smart Fee Estimation (estimatesmartfee)

A new RPC named estimatesmartfee is now available which returns a suitable
fee rate for transactions to use in order to have a high probability of them
being mined within a specified number of confirmations. The estimation is based
on actual network usage and thus varies according to supply and demand.

This is important in the context of the Lightning Network (LN) and, more
generally, it provides services and users with a mechanism to choose how to
handle network congestion. For example, payments that are high priority might
be willing to pay a higher fee to help ensure the transaction is mined more
quickly, while lower priority payments might be willing to wait longer in
exchange for paying a lower fee. This estimation capability provides a way to
obtain a fee that will achieve the desired result with a high probability.

Support for Whitelisting Inbound Peers

When peers are whitelisted via the --whitelist option, they will now be
allowed to connect even when they would otherwise exceed the maximum number of
peers. This is highly useful in cases where users have configured their wallet
to use SPV mode and only connect to dcrd instances that they control for
increased privacy and guaranteed service.

Several Speed Optimizations

Similar to previous releases, this release also contains several enhancements to
improve speed for the initial sync process, validation, and network operations.

In order to achieve these speedups, there is a lengthy one time database
migration, as previously mentioned, that typically takes anywhere from 30
minutes to an hour to complete depending on hardware.

Faster Tip Block Relay

Blocks that extend the current best chain are now relayed to the network
immediately after they pass the initial sanity and contextual checks, most
notably valid proof of work. This allows blocks to propagate more quickly
throughout the network, which in turn improves vote times.

UTXO Set Restructuring

The way the unspent transaction outputs are handled internally has been
overhauled to significantly decrease the time it takes to validate blocks and
transactions. While this has many benefits, probably the most important one
for most stakeholders is that votes can be cast more quickly which helps reduce
the number of missed votes.

RPC Server Changes

New Chain State Query RPC (getblockchaininfo)

A new RPC named getblockchaininfo is now available which can be used to query
the state of the chain including details such as its overall verification
progress during initial sync, the maximum supported block size, and that status
of consensus changes (deployments) which require stakeholder votes. See the
JSON-RPC API Documentation
for API details.

Removal of Vote Creation RPC (createrawssgen)

The deprecated createrawssgen, which was previously used to allow creating a
vote via RPC is no longer available. Votes are time sensitive and thus it does
not make sense to create them offline.

Updates to Block and Transaction RPCs

The getblock, getblockheader, getrawtransaction, and
searchrawtransactions RPCs now contain additional information such as the
extradata field in the header, the expiry field in transactions, and the
blockheight and blockindex of the block that contains a transaction if it
has been mined. See the JSON-RPC API Documentation
for API details.

Built-in Support for Enabling External TLS RPC Connections

A new command line parameter (--altdnsnames) and environment variable
(DCRD_ALT_DNSNAMES) can now be used before the first launch of drcd to specify
additional external IP addresses and DNS names to add during the certificate
creation that are permitted to connect to the RPC server via TLS. Previously,
a separate tool was required to accomplish this configuration.

Changelog

All commits since the last release may be viewed on GitHub here.

Protocol and network:

Transaction relay (memory pool):

RPC:

dcrd command-line flags and configuration:

Documentation:

Developer-related package and module changes:

Testing and Quality Assurance:

Misc:

Code Contributors (alphabetical order):

  • Corey Osman
  • Dave Collins
  • David Hill
  • Dmitry Fedorov
  • Donald Adu-Poku
  • ggoranov
  • githubsands
  • J Fixby
  • Jonathan Chappelow
  • Josh Rickmar
  • Matheus Degiovani
  • Sarlor
  • zhizhongzhiwai
Assets 2
Loading