Performance is not an Option - gRPC and Cassandra

transcript

In today's development ecosystem building a service oriented architecture based on a micro services is

common practice. With the rise of Big Data and Internet of Things applications making these services highly

performant services is no longer an option. In order to accomplish the scalability and performance

requirements that customers expect we are required to start thinking differently about how we architect and

build these applications in order to meet those demands.

This session will demonstrate a method for creating a highly performant service based application using

Google’s GRPC and Apache Cassandra in .NET. We will show how you can combine gRPC to minimize

communication overhead while leveraging Cassandra to optimize storage of time series data. We will explore

these concepts by creating an Internet of Things (IoT) application to demonstrate how you can effectively

meet the performance and scalability challenges posed by these new breeds of applications.

Abstract

Performance is not an OptionBuilding High performance Web Services with gRPC and Cassandra

June 9th, 2016

#build4prfrmnc

● What is gRPC

● What is Cassandra

● How to build a simple gRPC Microservice

● How to persist time series data in Cassandra

● Why you might want to use gRPC/Cassandra instead of a

more traditional REST/RDBMS for a Time-Series IoT

application

What I hope you take away

Dave BechbergerSenior Architect dave@experoinc.com @bechbd https://www.linkedin.com/in/davebechberger

About me

Expero - Bringing challenging product ideas to reality

Architecture & Development

Product Strategy

User Experience

DomainExpert

Expero - Select Clients

6Austin(HQ) • Houston • New York City • Founded 2003

What is gRPC?

● gRPC is a general purpose RPC framework

● Built on standards

● Free and Open Source

● Built for distributed systems

What is gRPC?

● Allows client to call methods on the server as if they were local

● Built for low latency highly scalable microservices

● Payload agnostic

● Bi-Directional Streaming

● Pluggable and Extensible

gRPC Architecture

Simple Model and Service Definition

Optimized Speed and Performance

Code Generation

What is Cassandra?

● Distributed Datastore

● Open Source Apache Project

● No Single Point of Failure

● Scalable

CAP Theorem - Pick 2● Consistency - all nodes see the same data

at the same time

● Availability - every requests receives a response

● Partition Tolerant - the system continues to operate even during network failures

ACID vs. BASERDBMS World

● Atomic - transactions are “all or nothing”

● Consistency - On completion all data is the same

● Isolated - transactions do not interfere with one another

● Durable - results of a transaction are permanent

NoSQL World

● Base Availability - The datastore works most of the time

● Soft State - Stores are not write consistent, data can differ between replicas

● Eventually Consistent - Stores become consistent over time

Cassandra Architecture

Hash Ring Architecture

● All nodes own a portion of the token ring

● All nodes know which token ranges belong to which nodes

● Partitioner generates a token from the Partition Key

● Tokens determine where data is located on the ring

How Tokens Work

Partitioner

Token:12

Client Driver

PK: Expero

Data Written

Data Replication

● Data replication is automatic

● Number of replicas is called the Replication Factor or RF

● Data is replicated between Data Centers

● Hinted Handoff

Data Replication in Action

Client

Write A

Data Written

Replica Written

Coordinator

Driver

Partitioner

Token:12

PK: Expero

What does it mean to be Eventually Consistent?

● Data will “eventually” match on all replicas, usually in terms of milliseconds

● Consistency Level or CL (11 for writes, 10 for reads)

● Tuning consistency affects performance and availability

● CL can be tuned for R/W performance on a per query basis using CQL

Why use Cassandra over your RDBMS?

● Performance

● Linearly Scalable

● Natively built as a distributed datastore

● Always-On Architecture

What is DataStax vs. Apache Cassandra?● Certified Cassandra – Delivers highest

quality Cassandra software for confidence and peace of mind for production environments

● Enterprise Security – Full protection for sensitive data

● Automatic Management Services – Automates key maintenance functions to keep the database running smoothly

● OpsCenter – Advanced management and monitoring functionality for production applications

● Expert Support – Answers and assistance from the Cassandra experts for all production needs

The Problem - Engine Monitoring

● Truck Engine Monitoring Software

● Currently ~ 1000 trucks taking readings every 10 seconds

● WebAPI REST on a SQL Server 2014 Database

● You were recently landed a huge new client Expero Trucking Inc.

● Sensor readings now 1/second and add geolocation (lat/long) data

● Adding 10,000 trucks.

● Minimize costs and zero downtime

The Requirements

● 100 measurements/second to 22,000 measurements/second

● Data load from ~35 MB/day to ~2.2 GB/day

● Your architecture needs to change

The Problem

The Solution - gRPC and Cassandra

Code Available Here https://github.com/experoinc/NDC-Oslo-2016/tree/master/NDC.Oslo

● Change SQL Server Database to a Cassandra Cluster

● Replace REST based services with gRPC services

Proposed Solution

Defining a Model and Service

Generating Client/Server Stubs

Model Definition Service Definition

Creating Cassandra KeySpace and Table

Connecting to Apache Cassandra using DataStax DriverDataStax Open Source C# Driver - https://github.com/datastax/csharp-driver

Writing Data to Cassandra

Reading Data From Cassandra

Time to See Some Running Code

Average Ping Time

Running in Oregon

Tradeoffs of gRPC and Cassandra

● Not for Browsers

● Chunk “Big” (>1MB ) Data

● No Nullable Data Types

● Not Production Yet

Tradeoffs of using gRPC

● No joins between tables

● No Ad-Hoc queries

● Minimal Aggregations

● Complexity

● Cassandra is Not Relational

Tradeoffs of using Cassandra

● gRPC

○ http://www.grpc.io/

○ https://developers.google.com/protocol-buffers/docs/proto3

● Cassandra

○ http://cassandra.apache.org/

○ http://www.planetcassandra.org/

○ https://academy.datastax.com/

○ http://www.datastax.com/

Learning More

Thank you, any Questions?