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Cloud Escape Velocity – Switching Cloud Providers

18 Dec

The term Escape Velocity is the speed needed to “break free” from a gravitational field without further propulsion according to Wikipedia.org.  Data Gravity as explained in THIS previous post is what attracts and builds more Data, Applications, and Services on Clouds.  Data Gravity also is what creates a high level of Escape Velocity to move to another Cloud.

Some background on why this post is timely:

A few days ago Amazon announced a new AWS service for importing VMware disk images (VMDKs) into EC2.  VMware already offered a method for converting EC2 instances through their Converter tool into Workstation VMs and with a 2nd pass conversion into ESX VMs.  While all of this sounds wonderful and it does have value, it brings to light an entirely different issue.  Only Stateful / Fully encapsulated applications can be moved around in this way.

Examples of sources of Cloud Gravity (App, Service, and Data Gravity Combined) on your specific Application.

If someone selects a Cloud provider and writes an application leveraging anything more than a handful of VMs, Data Gravity will make it virtually impossible to move to a new/different Cloud provider.  Don’t believe it?

See the Diagrams Below:

Here is a diagram of an app that has a Low Escape Velocity because of Lower Cloud Gravity:

Cloud Escape Velocity with Low Gravity

Below is a diagram of an app that has a High Escape Velocity because of High Cloud Gravity:

Cloud Escape Velocity with High Gravity

Some potential dependencies include:

Database with a specific API

Web Worker which serves as a web interface and uses internal Authentication (Your user logins are here!)

Application code that uses the Database and Web Workers specific APIs and/or depends on Low Latency and High Throughput access to them.

Here are a few additional things to think about:

– The longer (more time) an Application stays in a specific Cloud the more difficult it is to move.  Why?  Data Gravity increases due to more Mass (data being stored).  Imagine accumulating 100’s of GBs of Data, how easy will it be to shuffle/transfer that much data around?

– The more provider APIs and Services that you depend on the harder it is to move.  Why?  Because there are only two paths that can be taken in a move.  The first is to find another provider that has the exact same set of APIs and Services (this will limit your choices).  The second is to change or rewrite your application to take advantage of the new Cloud provider’s APIs and/or Services.

– Different providers have different charges for the consumption of the same resources.  Your current provider gives free usage of queues for applications. The provider you are looking to go to charges after the first X number of messages on the queue.  Now what do you do?  You will either pay more when you move, rewrite your application to fit the new provider’s model, or pick another provider that has free queue usage.

– Different QoS guarantees from Cloud provider to Cloud provider.  Some Cloud providers offer SLAs with reimbursements for outages, others only offer best effort.  Some providers offer tiered Services, others only offer a single tier.  What happens if you want to move and you can’t get the minimum level of QoS that you need?

This is NOT an attempt to dissuade anyone from using Public Clouds (they are incredibly valuable and powerful), but I would like more people to go in eyes wide open.

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Data Gravity – in the Clouds

7 Dec

Today Salesforce.com announced Database.com at Dreamforce.  I realized that many could be wondering why they decided to do this and more so, why now?

The answer is Data Gravity.

Consider Data as if it were a Planet or other object with sufficient mass.  As Data accumulates (builds mass) there is a greater likelihood that additional Services and Applications will be attracted to this data. This is the same effect Gravity has on objects around a planet.  As the mass or density increases, so does the strength of gravitational pull.  As things get closer to the mass, they accelerate toward the mass at an increasingly faster velocity.  Relating this analogy to Data is what is pictured below.

Data Gravity

Services and Applications can have their own Gravity, but Data is the most massive and dense, therefore it has the most gravity.  Data if large enough can be virtually impossible to move.
What accelerates Services and Applications to each other and to Data (the Gravity)?
Latency and Throughput, which act as the accelerators in continuing a stronger and stronger reliance or pull on each other.  This is the very reason that VMforce is so important to Salesforce’s long term strategy.  The diagram below shows the accelerant effect of Latency and Throughput, the assumption is that the closer you are (i.e. in the same facility) the higher the Throughput and lower the Latency to the Data and the more reliant those Applications and Services will become on Low Latency and High Throughput.
Note:  Latency and Throughput apply equally to both Applications and Services
How does this all relate back to Database.com?  If Salesforce.com can build a new Data Mass that is general purpose, but still close in locality to its other Data Masses and App/Service Properties, it will be able to grow its business and customer base that much more quickly.  It also enables VMforce to store data outside of the construct of ForceDB (Salesforce’s core database) enabling knew Adjacent Services with persistence.
The analogy holds with the comparison of your weight being different on one planet vs. another planet to that of services and applications (compute) having different weights depending on Data Gravity and what Data Mass(es) they are associated with.
Here is a 3D video depicting what I diagrammed at the beginning of the post in 2D.

 

More on Data Gravity soon (There is a formula in this somewhere)

An Administrator’s view of Open PaaS and VMforce

23 Nov

After posting about How Development works on Open PaaS and VMforce, I felt it was time to provide an equivalent view from an Administrator’s perspective. Before going deep, I thought I would provide a comparison of what things look like between the Developer’s view of things vs. the Administrator’s.

Comparison of Developer vs. Admin View


Please note that this is derived information and in some cases speculative (but I bet I’m close)
Starting at the top:

  • The URL and Mapping matches a DNS entry with an External IP (Host), a Path, and a Port to Access the Application
  • The Application contains an App Instance matching the Virtual Machine with a Workload (Potentially multiple Workloads)
  • The Internal IP operates off of the assumption that the VM is either multi-homed or has a NAT based interface with an Inside and Outside Address
  • The Service Instance matches a VM with a specific Running Service inside. This could be a shared Service instance or a Multi-User/Tenant Service Instance (There isn’t enough info. from what I have found to know which)
  • The Service Catalog is the equivalent of a Template/Gold Image based VM (in the describe model)
  • There are several different ways VMware could choose to implement isolation and multi-tenancy.

The diagram below gives an Administrator’s view of Open PaaS and its implementation inside of VMforce. The current implemented resource model shows a quota system as the chosen way of limiting/controlling consumption of resources in the Open PaaS Cloud.

Administrator's View of Open PaaS / VMforce

The Account is the line between where the Administrator turns over the resources to the Developer. This seems like it would create an environment like the wild west, but this is a deceptively simple view. The Architects and Administrators both have the ability to constrain the system before any code is pushed into it. This is achieved by decisions on what types of code can supported in the system, potentially constraining allowed frameworks, available services, the ability to create services, and allocated resources. Quota based allocated resources include number of CPU cores, Memory, and Disk space.

From what I have been able to find so far, there is a focus on isolation by Account using a quota system.
The strongest isolation model would be to assign each workload its own VM, this however would consume far more resources than isolation at a process level (a typical trade-off). Implementing isolation at a process level would work well but you wouldn’t want all Workloads (App Instances) for a single Application running in a single VM, because if the VM fails so does your Application. As more is revealed, I will provide more indepth information on how isolation and distribution is done.

There is also an unknown as to if and how a load-balancing mechanism is implemented. I haven’t come across how/if this is implemented, perhaps this is done in the Mapping (via. DNS/round robin?). This is purely speculative.

AppCloud appears to be VMware Open PaaS Cloud backend name

20 Nov

As I continue to go through VMC related code, I have come across a few code entries talking about AppCloud.  At first I thought this might be a reference to EngineYard’s AppCloud solution. This brought to mind the rumors I mentioned in previous posts, but after further digging and reading the following code and code comments:

AppCloud Gist

Code references to AppCloud


I am fairly convinced that AppCloud is referring to the Open PaaS Cloud Controller (and possibly some of the other components collectively), not EngineYard’s AppCloud. The big question in my mind is when will the first version of “AppCloud” be launched/shipped/released.

How Development works on Open PaaS & VMforce

14 Nov

After having gone through the materials available (both the easy to find and the difficult to find) I have created what should be an accurate view of what the environments inside a VMware Open PaaS and VMforce world should look like.  In this post is a series of diagrams that I have created based on what I have concluded is the way the current system works.

Developer's overview of Open PaaS & VMforce

In the diagram above, starting at the top:

  • Organization Context – This is likely a sub-Cloud of the overall Cloud, but I haven’t been able to clarify this in the code yet.  It provides authentication and determines which services are available to be used and shared amongst User Accounts (aka Service Domains)
  • User Account – This is done by registering an e-mail address and a password, each account is allocated a quota which is controlled by an administrator.
  • URL – This is how external Applications, Users, APIs, etc. access the Application
  • Mapping – Connects the URL to the Application (Allowing Applications to be Switched beneath the URL)
  • Application – Also know as a “Droplet”, is made up of App Instances and connect to Service Instances
  • Service Instances – Are useable/consumable/invoked instances of services from the Service Catalog
  • Service Catalog – This is the listing of all available services that can currently be invoked for use by an Application

Logical Diagram of Open PaaS - VMforce

The above diagram shows a slightly more filled out Service Catalog. These are the services that were provided as examples by the VMware presentations and documentation that I have seen so far.  The diagram also shows an even larger number of applications running, although each only has a single App Instances associated with it.

Detailed Logical Diagram of a more realistic example

In this diagram (above), there are two URLs each providing access to an Application.  The first application on the left has a single Application Instance and that App Instance is bound (see Binding Labels) to a MySQL Instance (Service Instance) and a RabbitMQ Instance (Service Instance).  The two Service Instances are created from the Service Catalog’s MySQL and RabbitMQ entries.

The second Application has three App Instances inside of it, all of which are bound to the SAME RabbitMQ Instance that the first Application is (this means that the two Applications can share information through the RabbitMQ Instance).  The MySQL Instance is a separate MySQL Instance from the first Application MySQL Instance, although both are based/invoked from the MySQL Service in the Service Catalog.  The Redis, Memcache, and MongoDB instances are all bound to each of the App Instances in the second application and are used by all three instances.

Diagram of Open PaaS - VMforce Service Tiers

The final Diagram is from information I came across while digging through the VMC Ruby code.  The code has fields in it for “Service Tiers”, which based on some poking around on Salesforce’s website, I came up with the above possibilities.  I don’t know if this is 100% accurate, but based on the information I think it provides a pretty reasonable approach to exposing provider services to Developers looking to write code on a Cloud platform such as VMforce.

There are several more interesting things that I have come across since I began going through the code.  I will be blogging about them soon.

Walk-through of the VMforce / Cloud OS / OpenPaaS Demo

13 Nov

This post attempts to walk-through the demo that was shown at the Ruby Conference.  I was not actually at the conference, but I am reconstructing what happened based on materials and information that was tweeted and the presentation materials.

Diagram of VMware Cloud OS - PaaS - VMforce Demo CLI Walk-through

The walk-through above shows a sophisticated PaaS layer (reminding me of the Google AppEngine PaaS) where code is uploaded/pushed and then inspected and compiled.  The resulting “App Instance” (also referred to as a “Slug” in Heroku terms) is ready to respond to requests.  Can’t service enough requests with just one App Instance?  Type “vmc instances fu 5” and instead of a single App Instance, the App Instance clones/copies/ Scales Out to 5 instances.

Need to Scale Down from 5 App Instances to 3 because demand has fallen?  “vmc instances fu 3” Scales Down the App Instances from 5 to 3 killing the last 2 App Instances – 3 and 4 (note that instances are numbered 0-4).

 

Diagram of VMware Cloud OS - PaaS - VMforce Demo CLI Walk-through - 2

Now the requests have fallen to the point where there is only 1 App Instance needed, so the command “vmc instances fu 1” shrinks (Scales Down) the App Instances from 3 to 1.  Now we look to see where the fu Application actually is resource utilization wise (This is the point where we see the overlap with the underlying VM) by typing “vmc stats fu”

This allows a Developer on a Public Cloud – in the above case vCloudLabs.com is hosted by Terremark (using vCloud if I had to guess) to deploy their code with little to NO knowledge of the underlying Infrastructure beneath (IaaS).  This ultimately mirrors the functionality of what VMware’s Cloud OS will provide to  Private Clouds and the Enterprise Development groups inside them.  What is demoed is supposed to be the same as the system was designed for VMforce in Salesforce.com ‘s Data Center as well.

VMware quietly shows Cloud OS, OpenPaaS, and VMforce at Ruby Conference

13 Nov

Yesterday, VMware previewed the first concrete evidence that they are moving forward on the OpenPaaS initiative, the VMware Cloud OS, and VMforce at the 2010 Ruby Conference in New Orleans. At the conference Derek Collison demonstrated an early preview of the VMware Cloud OS via. a command line interface that he and Ezra Zygmuntowicz created.

The demonstration included showing Ruby code being auto deployed (pushed) into an a VM (where it becomes an App), coming online and then scaling both up and down in real-time. Also shown in the presentation itself was a screenshot of the control panel providing a view into what is being referred to as an application centric view of PaaS.

VMware Cloud OS Dashboard

In addition, the architecture was described, covering how the system is coordinated for auto-scaling and how resources are controlled.  Below is the high level architecture that was presented, a more detailed and in-depth walkthrough of how the system works will be published on this blog tomorrow.

VMware Cloud OS / OpenPaaS Architecture

VMware is moving quickly to fully support all modern/popular languages in the Cloud OS, including:

  • Ruby
  • Java
  • Node.js
  • Python
  • .NET
  • and more!

This strategy is critical to VMware being able to uplift itself from being considered a purely infrastructure company, to that of a Platform company (beyond owning SpringSource).  It is also important to VMware in attempting to grab developer mindshare by trying to better meet the capabilities that developers have traditionally been going to the Public Cloud for, by enabling Enterprises to provide those same capabilities internally (real Private Clouds).

Several more posts to follow very soon…