ac002d6422
This implements an efficient and zero-allocation script tokenizer that is exported to both provide a new capability to tokenize scripts to external consumers of the API as well as to serve as a base for refactoring the existing highly inefficient internal code. It is important to note that this tokenizer is intended to be used in consensus critical code in the future, so it must exactly follow the existing semantics. The current script parsing mechanism used throughout the txscript module is to fully tokenize the scripts into an array of internal parsed opcodes which are then examined and passed around in order to implement virtually everything related to scripts. While that approach does simplify the analysis of certain scripts and thus provide some nice properties in that regard, it is both extremely inefficient in many cases, and makes it impossible for external consumers of the API to implement any form of custom script analysis without manually implementing a bunch of error prone tokenizing code or, alternatively, the script engine exposing internal structures. For example, as shown by profiling the total memory allocations of an initial sync, the existing script parsing code allocates a total of around 295.12GB, which equates to around 50% of all allocations performed. The zero-alloc tokenizer this introduces will allow that to be reduced to virtually zero. The following is a before and after comparison of tokenizing a large script with a high opcode count using the existing code versus the tokenizer this introduces for both speed and memory allocations: benchmark old ns/op new ns/op delta BenchmarkScriptParsing-8 63464 677 -98.93% benchmark old allocs new allocs delta BenchmarkScriptParsing-8 1 0 -100.00% benchmark old bytes new bytes delta BenchmarkScriptParsing-8 311299 0 -100.00% The following is an overview of the changes: - Introduce new error code ErrUnsupportedScriptVersion - Implement zero-allocation script tokenizer - Add a full suite of tests to ensure the tokenizer works as intended and follows the required consensus semantics - Add an example of using the new tokenizer to count the number of opcodes in a script - Update README.md to include the new example - Update script parsing benchmark to use the new tokenizer |
||
---|---|---|
.github/workflows | ||
addrmgr | ||
blockchain | ||
btcec | ||
btcjson | ||
chaincfg | ||
cmd | ||
connmgr | ||
database | ||
docs | ||
integration | ||
limits | ||
mempool | ||
mining | ||
netsync | ||
peer | ||
release | ||
rpcclient | ||
txscript | ||
wire | ||
.gitignore | ||
btcd.go | ||
CHANGES | ||
config.go | ||
config_test.go | ||
doc.go | ||
Dockerfile | ||
go.mod | ||
go.sum | ||
goclean.sh | ||
LICENSE | ||
log.go | ||
params.go | ||
README.md | ||
rpcadapters.go | ||
rpcserver.go | ||
rpcserverhelp.go | ||
rpcserverhelp_test.go | ||
rpcwebsocket.go | ||
sample-btcd.conf | ||
server.go | ||
service_windows.go | ||
signal.go | ||
signalsigterm.go | ||
upgrade.go | ||
upnp.go | ||
version.go |
btcd
btcd is an alternative full node bitcoin implementation written in Go (golang).
This project is currently under active development and is in a Beta state. It is extremely stable and has been in production use since October 2013.
It properly downloads, validates, and serves the block chain using the exact rules (including consensus bugs) for block acceptance as Bitcoin Core. We have taken great care to avoid btcd causing a fork to the block chain. It includes a full block validation testing framework which contains all of the 'official' block acceptance tests (and some additional ones) that is run on every pull request to help ensure it properly follows consensus. Also, it passes all of the JSON test data in the Bitcoin Core code.
It also properly relays newly mined blocks, maintains a transaction pool, and relays individual transactions that have not yet made it into a block. It ensures all individual transactions admitted to the pool follow the rules required by the block chain and also includes more strict checks which filter transactions based on miner requirements ("standard" transactions).
One key difference between btcd and Bitcoin Core is that btcd does NOT include wallet functionality and this was a very intentional design decision. See the blog entry here for more details. This means you can't actually make or receive payments directly with btcd. That functionality is provided by the btcwallet and Paymetheus (Windows-only) projects which are both under active development.
Requirements
Go 1.16 or newer.
Installation
https://github.com/btcsuite/btcd/releases
Linux/BSD/MacOSX/POSIX - Build from Source
-
Install Go according to the installation instructions here: http://golang.org/doc/install
-
Ensure Go was installed properly and is a supported version:
$ go version
$ go env GOROOT GOPATH
NOTE: The GOROOT
and GOPATH
above must not be the same path. It is
recommended that GOPATH
is set to a directory in your home directory such as
~/goprojects
to avoid write permission issues. It is also recommended to add
$GOPATH/bin
to your PATH
at this point.
- Run the following commands to obtain btcd, all dependencies, and install it:
$ cd $GOPATH/src/github.com/btcsuite/btcd
$ GO111MODULE=on go install -v . ./cmd/...
- btcd (and utilities) will now be installed in
$GOPATH/bin
. If you did not already add the bin directory to your system path during Go installation, we recommend you do so now.
Updating
Linux/BSD/MacOSX/POSIX - Build from Source
- Run the following commands to update btcd, all dependencies, and install it:
$ cd $GOPATH/src/github.com/btcsuite/btcd
$ git pull
$ GO111MODULE=on go install -v . ./cmd/...
Getting Started
btcd has several configuration options available to tweak how it runs, but all of the basic operations described in the intro section work with zero configuration.
Linux/BSD/POSIX/Source
$ ./btcd
IRC
- irc.libera.chat
- channel #btcd
- webchat
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.
Release Verification
Please see our documentation on the current build/verification process for all our releases for information on how to verify the integrity of published releases using our reproducible build system.
License
btcd is licensed under the copyfree ISC License.