The Silver Searcher
A code searching tool similar to ack, with a focus on speed.
Do you know C? Want to improve ag? I invite you to pair with me.
What's so great about Ag?
- It is an order of magnitude faster than
ack.
- It ignores file patterns from your
.gitignore and .hgignore.
- If there are files in your source repo you don't want to search, just add their patterns to a
.ignore file. (*cough* *.min.js *cough*)
- The command name is 33% shorter than
ack, and all keys are on the home row!
Ag is quite stable now. Most changes are new features, minor bug fixes, or performance improvements. It's much faster than Ack in my benchmarks:
ack test_blah ~/code/ 104.66s user 4.82s system 99% cpu 1:50.03 total
ag test_blah ~/code/ 4.67s user 4.58s system 286% cpu 3.227 total
Ack and Ag found the same results, but Ag was 34x faster (3.2 seconds vs 110 seconds). My ~/code directory is about 8GB. Thanks to git/hg/ignore, Ag only searched 700MB of that.
There are also graphs of performance across releases.
How is it so fast?
- Ag uses Pthreads to take advantage of multiple CPU cores and search files in parallel.
- Files are
mmap()ed instead of read into a buffer.
- Literal string searching uses Boyer-Moore strstr.
- Regex searching uses PCRE's JIT compiler (if Ag is built with PCRE >=8.21).
- Ag calls
pcre_study() before executing the same regex on every file.
- Instead of calling
fnmatch() on every pattern in your ignore files, non-regex patterns are loaded into arrays and binary searched.
I've written several blog posts showing how I've improved performance. These include how I added pthreads, wrote my own scandir(), benchmarked every revision to find performance regressions, and profiled with gprof and Valgrind.
Installing
macOS
brew install the_silver_searcher
or
port install the_silver_searcher
Linux
Ubuntu >= 13.10 (Saucy) or Debian >= 8 (Jessie)
apt-get install silversearcher-ag
Fedora 21 and lower
yum install the_silver_searcher
Fedora 22+
dnf install the_silver_searcher
RHEL7+
yum install epel-release.noarch the_silver_searcher
Gentoo
emerge -a sys-apps/the_silver_searcher
Arch
pacman -S the_silver_searcher
Slackware
sbopkg -i the_silver_searcher
openSUSE
zypper install the_silver_searcher
CentOS
yum install the_silver_searcher
NixOS/Nix/Nixpkgs
nix-env -iA silver-searcher
SUSE Linux Enterprise: Follow these simple instructions.
BSD
Windows
Win32/64
Unofficial daily builds are available.
winget
winget install "The Silver Searcher"
Notes:
- This installs a release of ag.exe optimized for Windows.
- winget is intended to become the default package manager client for Windows.
As of June 2020, it's still in beta, and can be installed using instructions there.
- The setup script in the Ag's winget package installs ag.exe in the first directory that matches one of these criteria:
- Over a previous instance of ag.exe from the same origin found in the PATH
- In the directory defined in environment variable bindir_%PROCESSOR_ARCHITECTURE%
- In the directory defined in environment variable bindir
- In the directory defined in environment variable windir
Chocolatey
choco install ag
MSYS2
pacman -S mingw-w64-{i686,x86_64}-ag
Cygwin
Run the relevant setup-*.exe, and select "the_silver_searcher" in the "Utils" category.
Building from source
Building master
Install dependencies (Automake, pkg-config, PCRE, LZMA):
macOS:
brew install automake pkg-config pcre xz
or
port install automake pkgconfig pcre xz
Ubuntu/Debian:
apt-get install -y automake pkg-config libpcre3-dev zlib1g-dev liblzma-dev
Fedora:
yum -y install pkgconfig automake gcc zlib-devel pcre-devel xz-devel
CentOS:
yum -y groupinstall "Development Tools"
yum -y install pcre-devel xz-devel zlib-devel
openSUSE:
zypper source-install --build-deps-only the_silver_searcher
Windows: It's complicated. See this wiki page.
Run the build script (which just runs aclocal, automake, etc):
./build.sh
On Windows (inside an msys/MinGW shell):
make -f Makefile.w32
Make install:
sudo make install
Building a release tarball
GPG-signed releases are available here.
Building release tarballs requires the same dependencies, except for automake and pkg-config. Once you've installed the dependencies, just run:
./configure
make
make install
You may need to use sudo or run as root for the make install.
Editor Integration
Vim
You can use Ag with ack.vim by adding the following line to your .vimrc:
let g:ackprg = 'ag --nogroup --nocolor --column'
or:
let g:ackprg = 'ag --vimgrep'
Which has the same effect but will report every match on the line.
Emacs
You can use ag.el as an Emacs front-end to Ag. See also: helm-ag.
TextMate
TextMate users can use Ag with my fork of the popular AckMate plugin, which lets you use both Ack and Ag for searching. If you already have AckMate you just want to replace Ack with Ag, move or delete "~/Library/Application Support/TextMate/PlugIns/AckMate.tmplugin/Contents/Resources/ackmate_ack" and run ln -s /usr/local/bin/ag "~/Library/Application Support/TextMate/PlugIns/AckMate.tmplugin/Contents/Resources/ackmate_ack"
Other stuff you might like
- Ack - Better than grep. Without Ack, Ag would not exist.
- ack.vim
- Exuberant Ctags - Faster than Ag, but it builds an index beforehand. Good for really big codebases.
- Git-grep - As fast as Ag but only works on git repos.
- fzf - A command-line fuzzy finder
- ripgrep
- Sack - A utility that wraps Ack and Ag. It removes a lot of repetition from searching and opening matching files.
The Silver Searcher（ag）是一款命令行代码搜索工具，功能类似 ack，主打速度快。