No Huddle Offense

"Individual commitment to a group effort-that is what makes a team work, a company work, a society work, a civilization work."

Insight driven resource management & scheduling

July 25th, 2016 • Comments Off on Insight driven resource management & scheduling

Future data center resource and workload managers – and their [distributed]schedulers – will require a new key integrate capability: analytics. Reason for this is the the pure scale and the complexity of the disaggregation of resources and workloads which requires getting deeper insights to make better actuation decisions.

For data center management two major factors play a role: the workload (processes, tasks, containers, VMs, …) and the resources (CPUs, MEM, disks, power supplies, fans, …) under control. These form the service and resource landscape and are specific to the context of the individual data center. Different providers use different (heterogeneous) hardware (revisions) resource and have different customer groups running different workloads. The landscape overall describes how the entities in the data center are spatially connected. Telemetry systems allow for observing how they behave over time.

The following diagram can be seen as a metaphor on how the two interact: the workload create a impact on the landscape. The box represent a simple workload having an impact on the resource landscape. The landscape would be composed of all kind of different entities in the data center: from the air conditioning facility all the way to the CPU. Obviously the model taken here is very simple and in real-life a service would span multiple service components (such as load-balancers, DBs, frontends, backends, …). Different kinds of workloads impact the resource landscape in different ways.

landscape_gravity

(Click to enlarge)

Current data center management systems are too focused on understanding resources behavior only and while external analytics capabilities exists, it becomes crucial that these capabilities need to move to the core of it and allow for observing and deriving insights for both the workload and resource behavior:

Deriving insights on how workloads behave during the life-cycle, and how resources react to that impact, as well as how they can enhance the service delivery is ultimately key to finding the best match between service components over space and time. Better matching (aka actually playing Tetris – and smartly placing the title on the playing field) allows for optimized TCO given a certain business objective. Hence it is key that the analytical capabilities for getting insights on workload and resource behavior move to the very core of the workload and resource management systems in future to make better insightful decisions. This btw is key on all levels of the system hierarchy: on single resource, hosts, resource group and cluster level.

Note: parts of this were discussed during the 9th workshop on cloud control.

Autopiloting the data center

March 21st, 2016 • 1 Comment

Orchestration and Scheduling are not the newest topics, in fact they have been used in distributed systems forever (as in a couple of decades :-)). Systems like Mesos and Kubernetes (or offerings like Mantl) have brought advancements when it comes to dealing with scale. Other systems have a great background in scheduling and offer many (read a whole lot) policies for the same, this includes technologies like Grid Engine, LSF/OpenLava, etc.. Actually some of these technologies integrate with each other (like navops, Kubernetes and Mesos, OpenLava and Mesos, ), which makes it for example interesting when dealing with scheduling for space & order at the same time.

Next to pure demand, upcoming trends like CNCF & OCI as well as the introduction of Software Defined Infrastructure (SDI) drive the number of resources and services the Orchestrators and Controllers manage up. And the Question arises how to efficiently manage your data center – doing it by a human pressing a button is just not going to scale 🙂

Feedback control systems are a great start, however have some drawbacks. The larger the scale the more conflicts you might get between the feedback loops. The approaches might work up to rack level but probably not much beyond that. For large scale we need an approach which works along the lines of watch (e.g. by using snap), learn/decide (e.g. by using TAP) and act (See Jason Waxman’s keynote at OCP). This will eventually allow for a operatorless/humanless/driverless operations of the data center to support autonomous operations for scaling, healing and optimizing e.g. TCO.

Within Intel Labs we have therefore come up with the concept of a foreground and a background flow. Within a continuously running background flow we observe (if needed over long time-periods) the data center with its resources and services and try to derive & update models heuristics (read: rule of thumb) continuously using analytics/machine learning. Within a foreground flow – which sometimes is denoted the fast loop as it needs to perform – we can than score against those heuristics/models in actions plans/recipes.

The action plan/recipes describe a process on how we deal with a initial placement or re-balancing event. The scoring will allow for making better initial placement (adding a workload) as well as re-balancing decisions (how/what/when to kill, migrate or tune the infrastructure). How to derive an heuristics is explained in a paper referenced below – the example within that is about to learn how to best place a VNF so that is makes optimal use of platform features such as SR-IOV. Multiple other heuristics can easily be imagined, like learning how many cores a certain workload needs.

The following diagram shows the background and foreground flow.

 

(Click to enlarge)

(Click to enlarge)

 

The heuristics are stored in an Information Core which based on the environment it is deployed in tunes itself. We’ve defined the concepts described here in a paper submitted to the Middleware 2015 conference. The researchers from Umea (who also run this highly recommended workshop) have used it and demonstrate an example use case in the same paper. For an example on how a background flow can help informing the foreground flow read this short paper. (Excuses for the paywall :-))

I’ll follow-up with some more blog posts detailing certain aspects of our latest work/research, like how the landscape works.

Running a distributed native-cloud python app on a CoreOS cluster

September 21st, 2014 • 1 Comment

Suricate is an open source Data Science platform. As it is architected to be a native-cloud app, it is composed into multiple parts:

Up till now each part was running in a SmartOS zone in my test setup or run with Openhift Gears. But I wanted to give CoreOS a shot and slowly get into using things like Kubernetes. This tutorial hence will guide through creating: the Docker image needed, the deployment of RabbitMQ & MongoDB as well as deployment of the services of Suricate itself on top of a CoreOS cluster. We’ll use suricate as an example case here – it is also the general instructions to running distributed python apps on CoreOS.

Step 0) Get a CoreOS cluster up & running

Best done using VagrantUp and this repository.

Step 1) Creating a docker image with the python app embedded

Initially we need to create a docker image which embeds the Python application itself. Therefore we will create a image based on Ubuntu and install the necessary requirements. To get started create a new directory – within initialize a git repository. Once done we’ll embed the python code we want to run using a git submodule.

$ git init
$ git submodule add https://github.com/engjoy/suricate.git

Now we’ll create a little directory called misc and dump the python scripts in it which execute the frontend and execution node of suricate. The requirements.txt file is a pip requirements file.

 
$ ls -ltr misc/
total 12
-rw-r--r-- 1 core core 20 Sep 21 11:53 requirements.txt
-rw-r--r-- 1 core core 737 Sep 21 12:21 frontend.py
-rw-r--r-- 1 core core 764 Sep 21 12:29 execnode.py 

Now it is down to creating a Dockerfile which will install the requirements and make sure the suricate application is deployed:

 
$ cat Dockerfile
FROM ubuntu
MAINTAINER engjoy UG (haftungsbeschraenkt)

# apt-get stuff
RUN echo "deb http://archive.ubuntu.com/ubuntu/ trusty main universe" >> /etc/apt/sources.list
RUN apt-get update
RUN apt-get install -y tar build-essential
RUN apt-get install -y python python-dev python-distribute python-pip

# deploy suricate
ADD /misc /misc
ADD /suricate /suricate

RUN pip install -r /misc/requirements.txt

RUN cd suricate && python setup.py install && cd ..

Now all there is left to do is to build the image:

 
$ docker build -t docker/suricate .

Now we have a docker image we can use for both the frontend and execution nodes of suricate. When starting the docker container we will just make sure to start the right executable.

Note.: Once done publish all on DockerHub – that’ll make live easy for you in future.

Step 2) Getting RabbitMQ and MongoDB up & running as units

Before getting suricate up and running we need a RabbitMq broker and a Mongo database. These are just dependencies for our app – your app might need a different set of services. Download the docker images first:

 
$ docker pull tutum/rabbitmq
$ docker pull dockerfile/mongodb

Now we will need to define the RabbitMQ service as a CoreOS unit in a file call rabbitmq.service:

 
$ cat rabbitmq.service
[Unit]
Description=RabbitMQ server
After=docker.service
Requires=docker.service
After=etcd.service
Requires=etcd.service

[Service]
ExecStartPre=/bin/sh -c "/usr/bin/docker rm -f rabbitmq > /dev/null ; true"
ExecStart=/usr/bin/docker run -p 5672:5672 -p 15672:15672 -e RABBITMQ_PASS=secret --name rabbitmq tutum/rabbitmq
ExecStop=/usr/bin/docker stop rabbitmq
ExecStopPost=/usr/bin/docker rm -f rabbitmq

Now in CoreOS we can use fleet to start the rabbitmq service:

 
$ fleetctl start rabbitmq.service
$ fleetctl list-units
UNIT                    MACHINE                         ACTIVE  SUB
rabbitmq.service        b9239746.../172.17.8.101        active  running

The CoreOS cluster will make sure the docker container is launched and RabbitMQ is up & running. More on fleet & scheduling can be found here.

This steps needs to be repeated for the MongoDB service. But afterall it is just a change of the Exec* scripts above (Mind the port setups!). Once done MongoDB and RabbitMQ will happily run:

 
$ fleetctl list-units
UNIT                    MACHINE                         ACTIVE  SUB
mongo.service           b9239746.../172.17.8.101        active  running
rabbitmq.service        b9239746.../172.17.8.101        active  running

Step 3) Run frontend and execution nodes of suricate.

Now it is time to bring up the python application. As we have defined a docker image called engjoy/suricate in step 1 we just need to define the units for CoreOS fleet again. For the frontend we create:

 
$ cat frontend.service
[Unit]
Description=Exec node server
After=docker.service
Requires=docker.service
After=etcd.service
Requires=etcd.service

[Service]
ExecStartPre=/bin/sh -c "/usr/bin/docker rm -f suricate > /dev/null ; true"
ExecStart=/usr/bin/docker run -p 8888:8888 --name suricate -e MONGO_URI=<change uri> -e RABBITMQ_URI=<change uri> engjoy/suricate python /misc/frontend.py
ExecStop=/usr/bin/docker stop suricate
ExecStopPost=/usr/bin/docker rm -f suricate

As you can see it will use the engjoy/suricate image from above and just run the python command. The frontend is now up & running. The same steps need to be repeated for the execution node. As we run at least one execution node per tenant we’ll get multiple units for now. After bringing up multiple execution nodes and the frontend the list of units looks like:

 
$ fleetctl list-units
UNIT                    MACHINE                         ACTIVE  SUB
exec_node_user1.service b9239746.../172.17.8.101        active  running
exec_node_user2.service b9239746.../172.17.8.101        active  running
frontend.service        b9239746.../172.17.8.101        active  running
mongo.service           b9239746.../172.17.8.101        active  running
rabbitmq.service        b9239746.../172.17.8.101        active  running
[...]

Now your distributed Python app is happily running on a CoreOS cluster.

Some notes

Live football game analysis

December 23rd, 2013 • Comments Off on Live football game analysis

Note: I’m talking about American Football here 🙂

In previous posts I already showed how game statistics can be used to automatically which Wide receiver is the Qb’s favorite on which play, down and field position. Now let’s take this one step further and create a little system (using Suricate) which will make suggestions to a Defense Coordinator.

The following diagram will guide through the steps needed to create such a system:

Live game breakdown (Click to enlarge)

Live game breakdown (Click to enlarge)

Let’s start at the top. (Step 1) The User of Suricate will start with performing some simple steps. First a bunch of game statistics are uploaded (same as using in this post). Next also a stream is defined. In this case a URI for an AMQP broker (using CloudAMQP – RabbitMQ as a Service) is defined in the service. With this used defined data is provide to the service.

(Step 2) Now we start creating an analytics notebook. Suricate provides an interactive python console via your web browser which can easily be used to explore the data previously uploaded. Python Pandas and scikit-learn are both available within the Suricate service and can be used right away to accomplish this task:

Exploring game statistics (Click to enlarge)

Exploring game statistics (Click to enlarge)

Based on the data we can create a model which describes on which down, on which fieldposition a run or a pass play is performed. We can also store who is the favorite Wide receiver/Running back for those plays (see also). All this information is stored in a JSON data structure and saved using the SDK of Suricate (Step 3).

(Step 4) Now a little external python script needs to be written which grabs relatively ‘live’ game data from e.g. here. This script now simple continuously sends messages to the previously defined RabbitMQ broker. The messages contain the current play, fieldposition and distance togo information.

(Step 5) Now a processing python notebook needs to be written. This is a rather simple python script. It takes the new incoming messages and compares them to the model learned in step 2 & 3. Based on that suggestions can be displayed (Step 6a) – “e.g. watch out for Wes Welker on 3rd and long at own 20y line” or just some percentages for pass or run plays:

Processing notebook (Click to enlarge)

Processing notebook (Click to enlarge)

Next the information about the new play can be added to the game statics data file (Step 6b). Once this is done a new model can be created (Step 7) to get the most up to date models all the time.

With this overall system new incoming data is streamed in (continuous analytics), models updated and suggestions for a Defense Coordinator outputted. Disclaimer: some steps describe here are not yet in the github repository of suricate – most namely the continuously running of scripts.

Peyton’s favorite WO (Analytics-as-a-Service)

November 17th, 2013 • 1 Comment

Again a little excerpt on stuff you can do with the help of Suricate. Again we’ll look at play-by-play statistics. So no information on which play was performed, but just the outcomes of the plays. Still there is some information you can retrieve from that. Most importantly because it can be done automated without user interaction needed. Just upload the file, press a button and get the results:

Peyton's favorites (Click to enlarge)

Peyton’s favorites (Click to enlarge)

This time you are looking are a cluster analysis of players Peyton passed too in the game of week 1. First cluster represent players passed to on 1,2 & 3 down with up to 6 yards. The second cluster the goto-guys which did go for medium yardage and finally the WOs able to get a bunch of yards on the board.

So with simple scripts (few lines of code – which can be reused) it is possible to abstract information from just play-to-play statistics. I guess mostly important to Defense Coordinators who would love to get some information on the fly with the press of a button 🙂

Page 1 of 3123