b6d426241d
This commit is the first stage of several that are planned to convert
the blockchain package into a concurrent safe package that will
ultimately allow support for multi-peer download and concurrent chain
processing. The goal is to update btcd proper after each step so it can
take advantage of the enhancements as they are developed.
In addition to the aforementioned benefit, this staged approach has been
chosen since it is absolutely critical to maintain consensus.
Separating the changes into several stages makes it easier for reviewers
to logically follow what is happening and therefore helps prevent
consensus bugs. Naturally there are significant automated tests to help
prevent consensus issues as well.
The main focus of this stage is to convert the blockchain package to use
the new database interface and implement the chain-related functionality
which it no longer handles. It also aims to improve efficiency in
various areas by making use of the new database and chain capabilities.
The following is an overview of the chain changes:
- Update to use the new database interface
- Add chain-related functionality that the old database used to handle
- Main chain structure and state
- Transaction spend tracking
- Implement a new pruned unspent transaction output (utxo) set
- Provides efficient direct access to the unspent transaction outputs
- Uses a domain specific compression algorithm that understands the
standard transaction scripts in order to significantly compress them
- Removes reliance on the transaction index and paves the way toward
eventually enabling block pruning
- Modify the New function to accept a Config struct instead of
inidividual parameters
- Replace the old TxStore type with a new UtxoViewpoint type that makes
use of the new pruned utxo set
- Convert code to treat the new UtxoViewpoint as a rolling view that is
used between connects and disconnects to improve efficiency
- Make best chain state always set when the chain instance is created
- Remove now unnecessary logic for dealing with unset best state
- Make all exported functions concurrent safe
- Currently using a single chain state lock as it provides a straight
forward and easy to review path forward however this can be improved
with more fine grained locking
- Optimize various cases where full blocks were being loaded when only
the header is needed to help reduce the I/O load
- Add the ability for callers to get a snapshot of the current best
chain stats in a concurrent safe fashion
- Does not block callers while new blocks are being processed
- Make error messages that reference transaction outputs consistently
use <transaction hash>:<output index>
- Introduce a new AssertError type an convert internal consistency
checks to use it
- Update tests and examples to reflect the changes
- Add a full suite of tests to ensure correct functionality of the new
code
The following is an overview of the btcd changes:
- Update to use the new database and chain interfaces
- Temporarily remove all code related to the transaction index
- Temporarily remove all code related to the address index
- Convert all code that uses transaction stores to use the new utxo
view
- Rework several calls that required the block manager for safe
concurrency to use the chain package directly now that it is
concurrent safe
- Change all calls to obtain the best hash to use the new best state
snapshot capability from the chain package
- Remove workaround for limits on fetching height ranges since the new
database interface no longer imposes them
- Correct the gettxout RPC handler to return the best chain hash as
opposed the hash the txout was found in
- Optimize various RPC handlers:
- Change several of the RPC handlers to use the new chain snapshot
capability to avoid needlessly loading data
- Update several handlers to use new functionality to avoid accessing
the block manager so they are able to return the data without
blocking when the server is busy processing blocks
- Update non-verbose getblock to avoid deserialization and
serialization overhead
- Update getblockheader to request the block height directly from
chain and only load the header
- Update getdifficulty to use the new cached data from chain
- Update getmininginfo to use the new cached data from chain
- Update non-verbose getrawtransaction to avoid deserialization and
serialization overhead
- Update gettxout to use the new utxo store versus loading
full transactions using the transaction index
The following is an overview of the utility changes:
- Update addblock to use the new database and chain interfaces
- Update findcheckpoint to use the new database and chain interfaces
- Remove the dropafter utility which is no longer supported
NOTE: The transaction index and address index will be reimplemented in
another commit.
|
||
|---|---|---|
| addrmgr | ||
| blockchain | ||
| chaincfg | ||
| cmd | ||
| database | ||
| database2 | ||
| dcrec | ||
| dcrjson | ||
| docs | ||
| limits | ||
| mining | ||
| peer | ||
| release | ||
| txscript | ||
| wire | ||
| .gitignore | ||
| .travis.yml | ||
| blocklogger.go | ||
| blockmanager.go | ||
| chainindexer.go | ||
| CHANGES | ||
| config_test.go | ||
| config.go | ||
| cpuminer.go | ||
| dcrd.go | ||
| deps.txt | ||
| discovery.go | ||
| doc.go | ||
| dynamicbanscore_test.go | ||
| dynamicbanscore.go | ||
| glide.lock | ||
| glide.yaml | ||
| goclean.sh | ||
| LICENSE | ||
| log.go | ||
| mempool.go | ||
| mempoolerror.go | ||
| mining_test.go | ||
| mining.go | ||
| miningerror.go | ||
| mrunoncemap_test.go | ||
| mrunoncemap.go | ||
| params.go | ||
| policy_test.go | ||
| policy.go | ||
| README.md | ||
| rpcserver.go | ||
| rpcserverhelp_test.go | ||
| rpcserverhelp.go | ||
| rpcwebsocket.go | ||
| sample-dcrd.conf | ||
| server.go | ||
| service_windows.go | ||
| signal.go | ||
| signalsigterm.go | ||
| upgrade.go | ||
| upnp.go | ||
| version.go | ||
dcrd
[
]
(https://travis-ci.org/decred/dcrd) ![ISC License]
(http://img.shields.io/badge/license-ISC-blue.svg)
dcrd is a Decred full node implementation written in Go (golang).
This acts as a chain daemon for the Decred cryptocurrency. dcrd maintains the entire past transactional ledger of Decred and allows relaying of transactions to other Decred nodes across the world. To read more about Decred please see the project documentation.
Note: To send or receive funds and join Proof-of-Stake mining, you will also need dcrwallet.
This project is currently under active development and is in a Beta state. It is extremely stable and has been in production use since February 2016.
It is forked from btcd which is a bitcoin full node implementation written in Go. btcd is a ongoing project under active development. Because dcrd is constantly synced with btcd codebase, it will get the benefit of btcd's ongoing upgrades to peer and connection handling, database optimization and other blockchain related technology improvements.
Getting Started
- dcrd (and utilities) will now be installed in either
$GOROOT/binor$GOPATH/bindepending on your configuration. If you did not already add the bin directory to your system path during Go installation, we recommend you do so now.
Updating
Windows
Install a newer MSI
Linux/BSD/MacOSX/POSIX - Build from Source
-
Glide
Glide is used to manage project dependencies and provide reproducible builds. To install:
go get -u github.com/Masterminds/glide
Unfortunately, the use of glide prevents a handy tool such as go get from
automatically downloading, building, and installing the source in a single
command. Instead, the latest project and dependency sources must be first
obtained manually with git and glide, and then go is used to build and
install the project.
Getting the source:
For a first time installation, the project and dependency sources can be
obtained manually with git and glide (create directories as needed):
git clone https://github.com/decred/dcrd $GOPATH/src/github.com/decred/dcrd
cd $GOPATH/src/github.com/decred/dcrd
glide install
go install $(glide nv)
To update an existing source tree, pull the latest changes and install the matching dependencies:
cd $GOPATH/src/github.com/decred/dcrd
git pull
glide install
go install $(glide nv)
For more information about decred and how to set up your software please go to our docs page at docs.decred.org.
Contact
If you have any further questions you can find us at:
- irc.freenode.net (channel #decred)
- webchat
- forum.decred.org
- decred.slack.com
Issue Tracker
The integrated github issue tracker is used for this project.
Documentation
The documentation is a work-in-progress. It is located in the docs folder.
License
dcrd is licensed under the copyfree ISC License.