There are three easy to make mistakes in go. I present them here in the way they are often found in the wild, not in the way that is easiest to understand.
All three of these mistakes have been made in Kubernetes code, getting past code review at least once each that I know of.
What do these lines do? Make predictions and then scroll down.
func print(pi *int) { fmt.Println(*pi) }Holt-Winters smoother/forecaster for anomaly detection
Forecast threads a smooth curve through a noisy timeseries in a way that lets you visualize trends, cycles, and anomalies. It can be used as part of an automatic anomaly detection system for metric timeseries (that is, sequences of timestamped numerical values).
It accomplishes this using a variation of Holt-Winters forecasting -- more generally known as exponential smoothing. Forecast decomposes a noisy signal into level, trend, repetitive "seasonal" effects, and unexplained variation or noise. In this example, a "season" is a day long, and we model repeated day-over-day variation. The result is a smoothed version of the signal which may be used to forecast future values or detect unexpected variation. This approach has been successfully used for [network anomaly detection](https://www.usenix.org/legacy/event/lisa2000/full_papers/br
| CFLAGS = -std=c99 -Wall | |
| main : main.o | |
| .PHONY : test clean | |
| test : main | |
| ./$^ "*regex*" "*vtable*" < main.c | |
| clean : |
| #!/usr/bin/python | |
| import socket, ssl, select, time, re | |
| from thread import start_new_thread | |
| from struct import pack | |
| TYPE_ENUM = 0 | |
| TYPE_STRING = 2 | |
| TYPE_BYTES = TYPE_STRING | |
| def clean(s): |
The prep-script.sh will setup the latest Node and install the latest perf version on your Linux box.
When you want to generate the flame graph, run the following (folder locations taken from install script):
sudo sysctl kernel.kptr_restrict=0
# May also have to do the following:
# (additional reading http://unix.stackexchange.com/questions/14227/do-i-need-root-admin-permissions-to-run-userspace-perf-tool-perf-events-ar )
sudo sysctl kernel.perf_event_paranoid=0
| import json | |
| from jsonrpclib import Server | |
| switches = ["172.22.28.156", "172.22.28.157", "172.22.28.158"] | |
| username = "admin" | |
| password = "admin" | |
| # Going through all the switch IP addresses listed above | |
| for switch in switches: | |
| urlString = "https://{}:{}@{}/command-api".format(username, password, switch) |
| [ | |
| { | |
| "use_channel":true, | |
| "allow_empty_post_data":true, | |
| "app_id":"edaded98-5119-4c8a-afc1-de722da03562", | |
| "url":"http://chromecast.redbull.tv/receiver.php", | |
| "dial_enabled":true | |
| }, | |
| { | |
| "use_channel":true, |
I used Ruby and Minitest with my Blink(1) to TDD through this very big Kata. It was fun and a great learning experience. It did a good job of going slowly at first to get the basics and then ramping up. There is much left that I could do here for further practice.
| #!/usr/bin/env bash | |
| # | |
| # Example usage: | |
| # | |
| # $ VERSION=1.3 sudo ./goinst.sh | |
| if [ "$(id -u)" != "0" ]; then | |
| echo "This script must be run as root" 1>&2 | |
| exit 1 | |
| fi |
| Music For Hackers | |
| == | |
| To a hacker, there's something distracting about booting up a GUI to listen to your tunes. You live your life in the terminal, you treat the mouse like a high voltage tap. | |
| So give these commands a run in the terminal, and toss on your headphones. | |
| sudo apt-get install mplayer | |
| echo "alias defcon-start='nohup mplayer http://sfstream1.somafm.com:6200 > /dev/null 1>&2 &'" >> ~/.bashrc | |
| echo "alias defcon-stop='killall -9 mplayer'" >> ~/.bashrc |
