SO YOU THINK YOU CAN

S C A L E @lmacvittie @F5Networks

Why do we scale?

100 Milliseconds Slower

-1% SALES -0.2% SEARCHES -2% CONVERSION

$660M $45M $244M

H/T James Urquhart, SOASTA Data: Gartner, Walmart

1 Minute of Downtime

Data: Emerson Power

Costs an average of $7300

Average total cost of downtime per year across industries

PRODUCTIVITY IT PRODUCTIVITY LOST REVENUE

$53,608$140,543 $183,724

=

UP OUT

How do we scale today?

POLB(Plain Old Load Balancing)

We throw POLB in front of everything

But architectures and apps are changing

THENMONOLITHIC MICROSERVICES & APIs

NOW

And so are “users”

THENHumans

NOWHumans, Systems, Things

L7 LBLayer 7 Load Balancing

Modern Apps Need Modern Scale

Scaling Modern Apps

THEN

CHOOSING AN ALGORITHM

NOW

• Round Robin• Least Connections• Fastest Response

CHOOSING AN ARCHITECTURE

• Horizontal• Functional• Partitioning

Growth and Innovation

Architectural Debt

Software has technical Debt. Networks have architectural debt.

L7 LBScalability architectures based on Scale Cube

Horizontal Duplication Functional Decomposition

Data Partitioning (Sharding)

X-AXIS Y-AXIS Z-AXIS

• Like clustering• Leverages cloning (horizontal duplication) • Typically operates at layer 4 (TCP) • This is POLB

X-AXIS

Y-AXIS

• Like routing / URL dispatch• Uses identifiable variables (usually from HTTP headers) • Operates at layer 7 (HTTP)

/login/

/checkout/

/search/

Z-AXIS

/car/[A-M]/

/car/[N-U]/

/car/[V-Z]/

• Like sharding • Uses one or more identifiable variables (usually from HTTP headers) • Operates at layer 7 (HTTP)

API

API

API

API

qAPI Dispatch

qPOLB

API Façade

L7

qDevice Driven

(Dispatch)L7

L7

L7

API

API

API

API

API

API

API

Purpose Driven(functional decomposition)

q

/status

/update

/status

/update

/billing

/profile

/update

q

Capacity Driven(POLB)

Variations on a Theme

• Data Partitioning (Sharding) Architectures• URL/HTTP dispatch• Dynamic routing based on backend

data• Scaling by Functional Decomposition • API metering • App versioning / migration • API deprecation

L7 LBArchitecting

Scalability

Things to Consider Sooner Rather than Later

Is your API design well-suited to scaling in any way other than POLB?

How do you identify people, systems, and things?

How do you distinguish between API versions?

Multi-tenant or single tenant microservices?

The answers to these questions will impact your scaling architectural options*.

Emacs or vi? *Maybe not that last one.

How are you monitoring (and what are you measuring with it)?

THANK YOU!@lmacvittie @F5Networks

l.macvittie@f5.com