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ozooxo /
Last active Jun 18, 2019
Setup a dev docker environment on AWS

Basically just spawn a new EC2 instance. I choose ubuntu 18.04 server, as Amazon 2 ECS optimized image doesn't have free tier. Log into the instance by

$ ssh ubuntu@<ec2-instance-ip>

No need to install git. But to make git clone works (even for public repo) I need to add my RSA key in this EC2 instance to github. Just follow this link to do so.

Follow this link to install docker.

ozooxo / gist:9280304
Last active May 15, 2019
MPI always gives rank=0, size = 1
View gist:9280304

I accidentally installed multiple versions of MPI's (openmpi, mpich2, ...) in my Ubuntu 12.04 machine. I removed them all, and installed openmpi again; however, after fixing that (I never try before that), my MPI always gives rank=0, size = 1. The reason is that the removal process is incomplete, hence causes file sharing conflict. It can be seen from the following test

beta@landmark:~$ whereis mpicc
mpicc: /usr/bin/mpicc.mpich2 /usr/bin/mpicc.openmpi /usr/bin/mpicc
/usr/bin/X11/mpicc.mpich2 /usr/bin/X11/mpicc.openmpi /usr/bin/X11/mpicc

It turns out that the packages libmpich2-3 and libmpich2-dev failed to be removed. So after apt-get remove libmpich2-3 libmpich2-dev, everything goes fine.

ozooxo /
Last active Apr 30, 2019
Install LocalStack (Mac)
pip install --user localstack
brew install nose

Modify ~/.zshrc to add

export PATH="/Users/cynthia/Library/Python/3.6/bin:${PATH}"
ozooxo /
Last active Apr 24, 2019
Various related to `PATH` on Mac

Check the path of one executable:

type -a postgres

Check the path:

echo $PATH
ozooxo / gist:7568836
Created Nov 20, 2013
The ``smlnj`` package cannot be located by simply doing ``sudo apt-get install smlnj`` in ubuntu 12.04. It can be installed by running the following code.
View gist:7568836
beta@landmark:~$ sudo add-apt-repository ppa:hrzhu/smlnj-backport
beta@landmark:~$ sudo apt-get update
beta@landmark:~$ sudo apt-get install smlnj
beta@landmark:~$ sml
Standard ML of New Jersey v110.75 [built: Tue Aug 20 07:15:06 2013]
ozooxo /
Last active Jun 18, 2018
Python content manager executing order
import contextlib
def inner():
print("inner(): before yield")
yield "~~~message~~~"
print("inner(): after yield")
except Exception as e:
print("inner(): catch exception -- "+str(e))
View gist:faf6d4a30d41eac0b5f9a5e583e87ecd

Run default example:

$ ./gatling/bin/ -sf gatling/user-files/simulations/computerdatabase/ -s computerdatabase.BasicSimulation -m

For a minimal setup using, then one can run it using mvn gatling:test.

For using io.gatling.highcharts:gatling-highcharts-maven-archetype, it seems have problem to run inside of Eclipse (I can't "add scala nature" even if I follow this toturial. However, to make it working in IntelliJ IDEA is quite straightforward (add scala plugin is kind of the only thing which need to handle).

ozooxo /
Last active May 8, 2018
Multiple JDK on MacOS

Search Java version and install:

$ brew tap caskroom/versions

$ brew cask search java
==> Exact Match
java ✔
==> Partial Matches
charles-applejava          eclipse-javascript         java6                     netbeans-java-ee           yourkit-java-profiler
View gist:2a02684da960b4e610612ea6859114f5
The Linux users' guide to Mac OS X
How to Install and Dual Boot Linux and Mac OS
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