This is a short post that explains how to write a high-performance matrix multiplication program on modern processors. In this tutorial I will use a single core of the Skylake-client CPU with AVX2, but the principles in this post also apply to other processors with different instruction sets (such as AVX512).
Matrix multiplication is a mathematical operation that defines the product of
| -module(mymodule). | |
| start_link() -> | |
| gen_server:start_link({local, ?MODULE}, ?MODULE, [], []). | |
| ... | |
| crash() -> | |
| gen_server:cast(?MODULE, crash). | |
| ... | |
| handle_cast(crash,State) -> | |
| {stop, error, State}; | |
| ... |
| # In order for gpg to find gpg-agent, gpg-agent must be running, and there must be an env | |
| # variable pointing GPG to the gpg-agent socket. This little script, which must be sourced | |
| # in your shell's init script (ie, .bash_profile, .zshrc, whatever), will either start | |
| # gpg-agent or set up the GPG_AGENT_INFO variable if it's already running. | |
| # Add the following to your shell init to set up gpg-agent automatically for every shell | |
| if [ -f ~/.gnupg/.gpg-agent-info ] && [ -n "$(pgrep gpg-agent)" ]; then | |
| source ~/.gnupg/.gpg-agent-info | |
| export GPG_AGENT_INFO | |
| else |
No, seriously, don't. You're probably reading this because you've asked what VPN service to use, and this is the answer.
Note: The content in this post does not apply to using VPN for their intended purpose; that is, as a virtual private (internal) network. It only applies to using it as a glorified proxy, which is what every third-party "VPN provider" does.
| #!groovy | |
| # Best of Jenkinsfile | |
| # `Jenkinsfile` is a groovy script DSL for defining CI/CD workflows for Jenkins | |
| node { | |
| } |
Here's my own list of the interesting stuff announced during this year's WWDC, collected from the keynotes, various Apple docs, blog posts and tweets.
If you're planning to watch the videos, I really recommend this Mac app that helps you download and watch them: https://github.com/insidegui/WWDC.
http://www.apple.com/osx/elcapitan-preview/
Since 2008 or 2009 I work on Apple hardware and OS: back then I grew tired of Linux desktop (which is going to be MASSIVE NEXT YEAR, at least since 2001), and switched to something that Just Works. Six years later, it less and less Just Works, started turning into spyware and nagware, and doesn't need much less maintenance than Linux desktop — at least for my work, which is system administration and software development, probably it is better for the mythical End User person. Work needed to get software I need running is not less obscure than work I'd need to do on Linux or othe Unix-like system. I am finding myself turning away from GUI programs that I used to appreciate, and most of the time I use OSX to just run a terminal, Firefox, and Emacs. GUI that used to be nice and unintrusive, got annoying. Either I came full circle in the last 15 years of my computer usage, or the OSX experience degraded in last 5 years. Again, this is from a sysadmin/developer ki
| import Foundation | |
| // Executes an array of blocks in parallel, but only returns after they're all done. | |
| func parallel(blocks: [() -> ()]) { | |
| let group = dispatch_group_create() | |
| let queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0) | |
| for block in blocks { | |
| dispatch_group_async(group, queue, block) | |
| } |
| import Foundation | |
| protocol SomeDelegateProtocol : class { | |
| func firstFunc() -> String | |
| func secondFunc() -> Bool | |
| func thirdFunc() -> Self | |
| } | |
| class MyClass { | |
| weak var delegate : SomeDelegateProtocol? |
