scottrigby

Demo: Flux Helm Operator -> Controller Migration

1. Create local cluster

   kind create cluster

2. Barebones flux2 install for demo

thiagozs

Testing with GoMock: A Tutorial

08/16/17 by  Sergey Grebenshchikov

No Comments

This is a quick tutorial on how to test code using the GoMock mocking library and the standard library testing package testing.

GoMock is a mock framework for Go. It enjoys a somewhat official status as part of the github.com/golang organization, integrates well with the built-in testing package, and provides a flexible expectation API.

reachlin

  // For all the confusing Prometheus configuration and
  // regular expressions,
  // explained in examples.


  // Remember, there are default values for each item if it's missing.
  // regex is (.*),
  // replacement is $1,
  // separator is ;
  // ,and action is replace 

williammartin

Iptables Regression Overview

We have encountered what appears to be a regression in iptables performance when appending many rules sequentially. We believe we have narrowed the regression to this but do not understand the implications of this commit. Summary provided below but more info available on this tracker story

Reproduction (credit @rosenhouse)

Set up

wrobstory

graste

File activity

strace -e trace=file -fp PID (file) or strace -e trace=desc -fp PID (file descriptors)

Common calls:

• access
• close – close file handle
• fchmod – change file permissions
• fchown – change file ownership

jvns

A lot of these are outright stolen from Edward O'Campo-Gooding's list of questions. I really like his list.

I'm having some trouble paring this down to a manageable list of questions -- I realistically want to know all of these things before starting to work at a company, but it's a lot to ask all at once. My current game plan is to pick 6 before an interview and ask those.

I'd love comments and suggestions about any of these.

I've found questions like "do you have smart people? Can I learn a lot at your company?" to be basically totally useless -- everybody will say "yeah, definitely!" and it's hard to learn anything from them. So I'm trying to make all of these questions pretty concrete -- if a team doesn't have an issue tracker, they don't have an issue tracker.

I'm also mostly not asking about principles, but the way things are -- not "do you think code review is important?", but "Does all code get reviewed?".

MohamedAlaa

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD

aliang

_complete_ssh_hosts ()
{
        COMPREPLY=()
        cur="${COMP_WORDS[COMP_CWORD]}"
        comp_ssh_hosts=`cat ~/.ssh/known_hosts | \
                        cut -f 1 -d ' ' | \
                        sed -e s/,.*//g | \
                        grep -v ^# | \
                        uniq | \
                        grep -v "\[" ;