pycon uk - ice: interactive cloud experimentation

NATIONAL AND KAPODISTRIAN UNIVESITY OF ATHENS DEPARTMENT OF INFORMATICS AND TELECOMMUNICATIONS

iCE Interactive cloud experimentation

in Python

George Lestaris @glestaris

PyCon UK20 September 2015

Coventry

Slides URLhttp://bit.ly/iCE-PyConUK

http://bit.ly/iCE-PyConUK

/me

• University of Athens, Greece

• iCE is part of my Bachelor thesis

• Software engineer in Pivotal, London

• Cloud Foundry Container technology

• ex-CERNois

2iCE: Interactive cloud experimentation in Python

The original problem (1/2)

• Most applications deployed in public cloud (AWS) use multiple VMs

• these VMs run services

• that communicate with each other

• in different rates


The original problem (2/2)


• So network performance (intra-cluster communication) within the same availability zone is very interesting and important

Web

Web

DBLoad balancer

DB

Web

Don’t really care

High bandwidthLow latency

Questions

• How do we measure intra-cluster network performance?

• How consistent it is through time?

• Can we make predictions on the network performance? - classification

• But remember requirements change all the time


The clique experiment (1/2)


• Run a number of VMs that send packets to each other

• Spawn n nodes in the same availability zone and same security group and subnetwork

• Run transfers between each pair

• Measure speed and monitor consistency of the results

• Is classification of VM-pairs into classes of “network distance” possible?

The clique experiment (2/2)

7

In the mathematical area of graph theory, a clique is subset of vertices of an undirected graph, such that its induced subgraph is complete; that is, every two distinct vertices in the clique are adjacent.Definition by Wikipedia "VR complex" by David Eppstein - Own work. Licensed under Public Domain via Commons

iCE: Interactive cloud experimentation in Python

Here classification seems easy


Slow class Fast

class

Back to the example


D

C

BF

A

E

Fast class

Slow class

Gauss, is that you?


Gauss, is that you?


• I need to run this experiment many times

• On different times of the day, different days of the week

• The results should be analysed and plotted

• If there is a classifier it needs to be fed with results

• The resulting model needs validation against any new results

• Automation, automation, automation

There will be iCE

12

because you shouldn’t run experiments by hand

http://github.com/glestaris/iCE

http://github.com/glestaris/iCE

iCE

• A tool that enables interactive experimentation.

• Experiment: a Python script file with:

• tasks: run remotely in each VM of the experiment

• runners: orchestrates tasks

• Interactive Shell

• AWS integration


Components• Registry: VMs (instances) that participate in an

experiment are registered under experimentation sessions

• Shell: facilitates spawning EC2 VMs and running experiments

• AWS integration: create and delete EC2 VMs that will register themselves to iCE

• Experiments: loads and runs experiments in remote instances


• Registry: VMs (instances) that participate in an experiment are registered under experimentation sessions

• Shell: facilitates spawning EC2 VMs and running experiments

• AWS integration: create and delete EC2 VMs that will register themselves to iCE

• Experiments: loads and runs experiments in remote instances


Half of it, for free

eve (Flask / Werkzeug) & requests

Fabric

boto

IPython

Sequence

16

RESTful API

VMVM

VMVM

VM

2. RegistrationPublic cloud

Client

1. Launches instances with EC2 API

4. SSH connections

3. Fetches list of registered instances


Static Demo

17

because your speaker is a coward

Creating VMs


$> ice-shell [DEBUG] Session id = 55fd40c4d8476f00211e12ae * ******************************************************************** * Welcome to iCE version v2.0.0! * You may leave this shell by typing `exit` or pressing Ctrl+D * Type `h <Command>` to get usage information for a given command, * or `h` for looking into a brief description of all commands. * ********************************************************************

$> ec2_create -n 5 -t t2.micro [DEBUG] Reservation r-149d56ed for 5 instances was created +-----------------+---------------+-----------------+-------------+----------+ | Id | AMI Id | Instance type | Public IP | Status | +-----------------+---------------+-----------------+-------------+----------+ | Reservation: r-149d56ed | +-----------------+---------------+-----------------+-------------+----------+ | i-6989d3c4 | ami-6e7bd919 | t2.micro | None | pending | |[...] | +-----------------+---------------+-----------------+-------------+----------+

Experimentation session

Waiting for VMs to come up and register


$> inst_wait -n 5 [DEBUG] 0 instances found, sleeping for 5 seconds... [...] [INFO] Instances are ready!

$> inst_ls [INFO] Found 5 instances +--------------------------+--------------+----------------------------------+ | Id | Public IP | Cloud Id | +--------------------------+--------------+----------------------------------+ | 55fd45b2d8476f00211e12b5 | 54.77.34.67 | eu-west-1.compute.amazonaws.com | | [...] | +--------------------------+--------------+----------------------------------+

$> ec2_ls [DEBUG] Reservation r-149d56ed for 5 instances was created +-----------------+---------------+-----------------+-------------+----------+ | Id | AMI Id | Instance type | Public IP | Status | +-----------------+---------------+-----------------+-------------+----------+ | Reservation: r-149d56ed | +-----------------+---------------+-----------------+-------------+----------+ | i-298cd684 | ami-6e7bd919 | t2.micro | 54.76.34.228| running | | [...] | +-----------------+---------------+-----------------+-------------+----------+

A simple experiment (1/2)


import ice # iCE package from fabric import api as fab # Fabric API

@ice.Runner def run(hosts): """A sample iCE runner. It gets the hostnames of all instances and prints them out.

:param dict hosts: Dictionary of ice.entities.Instances objects. """ # Get hostnames of all instances, through fab.execute # First argument: Python function # Second argument: List of hosts # It returns a dictionary with the task result as value. hostnames = fab.execute(get_hostname, hosts)

# Prints for key in hostnames: print hostnames[key]

21

@ice.Task def get_hostname(hosts): """A simple iCE task. It returns the FQDN hostname of the remote instance.

:param dict hosts: Dictionary of ice.entities.Instances objects. :rtype: str :return: The FQDN hostname. """ # Get the FQDN hostname from each node hostname = fab.run('hostname -f') return hostname

A simple experiment (2/2)


Loading and running an experiment


$> exp_load ./experiments/simple.py [DEBUG] About to load module 'simple' from path '/Users/george/di_dev/Thesis/iCE/experiments' [INFO] Module `./experiments/simple.py` is successfully loaded!

$> exp_ls simple > Module `simple`: Runners: * run: A sample iCE runner. It gets the hostnames of all instances and prints them out. [...]

Tasks: * get_hostname: A simple iCE task. It returns the FQDN hostname of the remote instance. […]

$> exp_run simple [[email protected]] run: hostname -f [[email protected]] out: ip-172-31-6-35.eu-west-1.compute.internal [...] ip-172-31-6-35.eu-west-1.compute.internal ip-172-31-6-36.eu-west-1.compute.internal [...]

Instead of a conclusion• Start with a research problem that interests you, make

some basic assumptions

• Be lazy and automate things

• always be ready to rerun experiments andreproduce results

• Use what is there

• Hope for the best and don’t be afraid to hit the wall fast


Talk / iCE feedback

pycon uk - ice: interactive cloud experimentation

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