Paradigm Shift: Leveraging
Private Cloud to Encourage Scale
and Resiliency at the App Layer
Sridhar Basam, Rick Melick, Andrew Mitry
Walmart Cloud Computing Platform
United States of America
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Scaling Out - Horizontal
• Adding additional units and have them act in concert
• Splitting workloads across Units
• Offers promise of linear, infinite scale
• Start with the easy parts of an app, then work on the hard (web/app vs DB tiers)
• Scalable, Commodity Block and Object Storage
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Elasticity
• Build more reliable and resilient products
• Dynamically scale to meet high demand
• Offers promise of linear, infinite scale
• Self healing applications over reliable infrastructure
• Plan for failure!
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Case Study:
Project: Comcast X1 Apps developed a new app for the Winter Olympics:
• Scaling as demand increases. 2X growth by year end.
Performance (time to market):
• Went from conception to production in under a month!
• (We've provisioned capacity for 1M more X1 STBs!)
Innovation:
• X1 built an internal tool leveraging jClouds to orchestrate OpenStack and was then
extended to bring elasticity to VMware too.
Costs:
• Time means money!
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Migrating to Cloud-Native
• Walmart.com in United States nearly 100% cloud-native.
• Site re-written while ramping up cloud capabilities.
• Not typical across the enterprise, and the roadmap is non-trivial.
• Transformation is an iterative process. As in nature, migration is a journey.
• Options?... Example…?
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The ACME Club
• ACME Club is fictional, but story based on real life.
• 5+ year old, ATG eCommerce, site for members; bare metal, Solaris SPARC.
• Migrate, 35, traditional, n-tier, monolithic, enterprise applications to x86 (RHEL). Put
site on private cloud. Start aligning to Cloud-Native.
• Business goals:
– 25% increase in operational efficiency (hours vs. weeks)
– 50% increase in site performance (page response; checkout)
– 75% decrease in hardware and data center costs
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Constraints
• The engineering architects had a couple of constraints when migrating:
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1.
All VMs were ephemeral in the company’s Private Cloud.
2.
“Block Storage,” was a cloud capability ACME Club chose not to invest
in at this time.
Approach
• Fully leverage OpenStack, along with OneOps, to transition and start transforming to
Cloud-Native. (Will discuss OneOps in a moment.)
• Create a new VLAN in each data center for the ACME eCommerce site.
• Put every application behind a VIP like a service. No host-to-host communications!
• Deploy all applications across two cloud regions in two data centers.
– Minimum 8 VMs per application.
Best Practice: Slightly over-provision non-native cloud applications in you Private Cloud
to force the problem of infrastructure stability up higher into the application stack.
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Challenges
• Apps requiring a single instance were not put onto the cloud. (2 of 30)
– With Block Storage, one additional application could have migrated.
Active/Passive configuration. Leverage dedicated Hypervisors using
host aggregates in OpenStack.
• eStore application used, “Sticky Sessions,” on the local VM.
– Compromise: Iff VM dies  customer has to re-login. The business
accepted this risk for the short-term.
Best Practice: Developers must move session management outside of the local
VMs - which are ephemeral.
– Options: Cassandra, Couchbase, etc.
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Crawl before walk: Incremental Wins for ACME Club
• Solaris to Linux; Physical to Virtual; self-service Agile Infrastructure; cloud platform
with application and service abstraction
Fewer assumptions made about environments. Thinking more elastic / ephemeral.
Horizontally scalable now vs. not before. 400% site availability improvement.
Decompose site into services which can be deployed and scaled independently,
while building new business capabilities as micro-services.
Design patterns to decouple the new from the old; creating API contracts that make
the legacy look like other micro-services.
Create a system around the edges; growing slowly, until the old can be retired.
Leverage existing services developed elsewhere in company’s private cloud for
business capabilities required by ACME eCommerce going forward.
DevOps culture; cross-functional, business capability teams that own the entire
development-to-operations lifecycle of their applications.
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OneOps
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Overview
• OneOps delivers continuous, cloud-based, application lifecycles and
empowers the enterprise to take on new projects and drive growth.
– OneOps is collaborative and visual.
– OneOps is model-driven.
– OneOps is a library of best-practices.
– OneOps is cloud platform abstraction.
• OneOps is Self-Service Agile Infrastructure: A platform for rapid, repeatable,
and consistent provisioning of app environments and backing services.
• OneOps enables continuous lifecycle management of complex, businesscritical application workloads on any cloud-based infrastructure.
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Lifecycle
• Define application workloads based on architectural and application
requirements.
• Provision environments by mapping the design output against operational
requirements.
• Monitor and control environments to maintain the required operational
levels.
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Workloads
• OneOps provides design catalogs for applications. Create custom designs and then
save them in a private catalog. Share those designs to drive architectural consistency
within the enterprise. Share them with the open source community.
OneOps provides operational best practices for many popular development
platforms, relational SQL databases, distributed NoSQL databases, messaging
systems, and many others. Create custom packs. Streamline operational policies
across the enterprise and share with the open source community.
OneOps provides a library of components. The components encapsulate lifecycle
management for many infrastructure resources (ex. servers, storage), software
artifacts (ex. OS packages, SCM repositories) and many others. In addition, create
and package custom components. Integrate with many cloud services, and share
custom components with the open source community.
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Portability
• Out of the box, OneOps supports many cloud platforms and providers –
public, private and local (single server). Examples:
– OpenStack™ cloud provider(s), of course! 
– Microsoft® Azure™
– Amazon® AWS™
– ?... (let’s see where the community takes it)
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Release Date
HOLIDAY
2015
OneOps.com
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About Walmart
• Divisions
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Walmart U.S.
Walmart International
Walmart Canada
Walmart Mexico
Walmart Chile
Walmart Supercenter
Walmart Discount Stores
Walmart Express
Walmart Neighborhood Market
Supermercado de Walmart
• Subsidiaries
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ASDA
Sam's Club
Vudu
Seiyu Group (Japan)
Yihaodian
Walmart de México y Centroamérica
@WalmartLabs
Walmart eCommerce
Walmart Neighborhood Market
Amigo Supermarkets
Massmart
Bompreço
Líder
Vital Statistics
Number of retail locations
Area served
Products
Revenue
Number of employees
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11,505 (October 7, 2015)
Worldwide
Apparel and footwear
electronics,specialty, cash &
carry,warehouse club, discount
store,hypermarket, supercenter,
superstore,supermarket, eCommerce
US $485.651 Billion (2014)
2.2 million worldwide (2015)
Make Walmart Your Walmart
Looking to explore your options?
• Walmart will be the first to deliver a seamless shopping experience at scale
for 260 million customers around the world.
• We are uniquely able to combine physical, online and mobile in a seamless
way that helps our customers save time while taking advantage of our
everyday low prices.
• Private Cloud is integral to empowering all of that, and we're looking for
technologists just like you.
We are hiring!
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Thank you!
• Sridhar Basam
Sridhar.Basam@walmart.com
• Rick Melick
RMelick@walmart.com
• Andrew Mitry
Andrew.Mitry@walmart.com / @amitry
Link to free book recommended in the session:
• http://pivotal.io/platform/migrating-to-cloud-native-applicationarchitectures-ebook
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