dhedlund

### Keybase proof

I hereby claim:

  * I am dhedlund on github.
  * I am dhedlund (https://keybase.io/dhedlund) on keybase.
  * I have a public key ASA0mGPwrTLRmvwITbe3clki11kFVvs-M_j2lLVEr_N1qAo

To claim this, I am signing this object:

dhedlund

class: center, middle

Dynamic Tracing with DTrace and SystemTap

---

DTrace

• Originally developed by Sun Microsystems, now Oracle

dhedlund

-module(intersection).
-compile(export_all).

intersection(ListA, ListB) ->
  intersection([], ListA, ListB).

intersection(Acc, [], ListB) ->
  Acc;

intersection(Acc, ListA, ListB) ->

dhedlund

Intro

Started by Thomas Hatch. Released under the Apache 2.0 license.

A good comparison of open-source configuration managements systems: [http://en.wikipedia.org/wiki/Comparison_of_open_source_configuration_management_software]

Thomas Hatch is also working on a project called butter that sits on top of salt for more complex operations such as cloud provisioning.

Talking Points

simplicity - At it's heart, salt is about making it easy to execute commands on a remote server...and fast.

dhedlund

Discovered an interesting algorithm for finding longest palindrome by playing with sequences in a text editor. Anyone know if there's a name for this algorithm?

Worst running time is O(n^2), which is better than the naive implementation of O(n^3) but not as efficient as some O(n) implementations (http://www.akalin.cx/longest-palindrome-linear-time). In general, assuming a non-pathological case, running time is around 2n * m where n is the length of the string and m is the mean length of all palindromes. For non-pathological cases (i.e. human sentences), n is often logarithmic (log n) and fast approaches 1 as n increases. This puts the average case complexity at around n log n and best-case n.

Developed as a solution to: http://www.therubygame.com/challenges/4

Algorithm

Original hand-work to discover a pattern:

dhedlund

# Maintainer: Simon Lipp <[email protected]>
# Contributor: Chris Bolton <http://scr.im/chris-kun>
# Contributor: Sergei Lebedev <superbobry at gmail dot com>

pkgname=coffee-script
pkgver=1.1.2
pkgrel=1
pkgdesc='CoffeeScript is a little language that compiles into JavaScript.'
arch=any
url=http://coffeescript.org

dhedlund

Generating an SSH Key

ssh-keygen -f ~/.ssh/github

Host github.com
  Hostname github.com
 IdentityFile ~/.ssh/github