crc-squared

README

crc-squared

crc-squared is a CLI and library for computing crc-32c checksums fast. The performance is achieved by:

• Parallelism
• The intel crc32 instruction
• mmap (optional)

Work in Progress

This repo is currently in its infancy. I currently wouldn't recommend you use it. Here is what I feel it needs before it's ready:

• Benchmarking
• Improving the parallelization: The current algorithm reaps a lot of the benefits of parallelism but there are some bottlenecks I could remove
• Documentation
• Removing the length requirement: Currently you need to know the length of what you want to checksum in advance. Ideally I would rework this so you could use just io.ReaderAt.

Installation

Linux

Debian (Ubuntu/Mint)

Download and install the .deb:

RELEASES=chanzuckerberg/crc-squared/releases
VERSION=$(curl https://api.github.com/repos/${RELEASES}/latest | jq -r .name | sed s/^v//)
DOWNLOAD=crc-squared_${VERSION}_linux_amd64.deb
curl -L https://github.com/${RELEASES}/download/v${VERSION}/${DOWNLOAD} -o crc-squared.deb
sudo dpkg -i crc-squared.deb
rm crc-squared.deb

Fedora (RHEL/CentOS)

Download and install the .rpm:

RELEASES=chanzuckerberg/crc-squared/releases
VERSION=$(curl https://api.github.com/repos/${RELEASES}/latest | jq -r .name | sed s/^v//)
DOWNLOAD=crc-squared_${VERSION}_linux_amd64.rpm
curl -L https://github.com/${RELEASES}/download/v${VERSION}/${DOWNLOAD} -o crc-squared.rpm
sudo rpm -i crc-squared.rpm
rm crc-squared.rpm

MacOS

Install via homebrew:

brew tap chanzuckerberg/tap
brew install crc-squared

Binary

Download the appropriate binary for your platform:

RELEASES=chanzuckerberg/crc-squared/releases
PLATFORM=#linux,darwin,windows
VERSION=$(curl https://api.github.com/repos/${RELEASES}/latest | jq -r .name | sed s/^v//)
DOWNLOAD=crc-squared_${VERSION}_${PLATFORM}_amd64.tar.gz
curl -L https://github.com/${RELEASES}/download/v${VERSION}/${DOWNLOAD} | tar zx

Windows

Follow instructions for binary, with windows.

Usage

Usage:
  crc-squared [OPTIONS] [Filepath]

Application Options:
  -p, --part-size=   Part size in bytes (default: 1024)
  -c, --concurrency= Concurrency
  -m, --mmap         Use mmap for downloads
      --version      Print the current version

Help Options:
  -h, --help         Show this help message

Arguments:
  Filepath:          file path to checksum