Who am I

System Architect

Team Lead

PHP Developer

Find me on

@alexhelkar

alexhelkar

https://github.com/alexhelkar

What does it mean

"to scale"?

Does it mean?

Or does it mean?

Often it means

"To scale"

Improve system metrics without changing the system*

* (dramaticaly)

Scale roadmap is predefined

by your stack and software architecture

Let's go!

Performance

Story

Code performance?

Blackfire.io & Symfony Blog

Current results:

Total request time: 18.4 ms

file_exists called: 7 times

Exec. time for file_exists: 460 µs

Expected results:

Exec/ time: ~17.6 µs

Total request time: ~18.3996 ms

PHP lang performance

Why a system is slow?

Scaling strategies

• Caching
• Queueing
• Reads/Writes Spliting
• Sharding

Caching

Typical Request Flow

DB Cache

Application Cache

Web Cache

Cache: Rule of thumb

Queueing

Queue as The Equalizer

Queue as The Equalizer

Problems?

Queue as Load Balancer

Problems?

Read/Write Splitting

Master-Slave replication

async/semi-sync

Writes

Reads

Reads

Problems?

Galera Replication

aka sync replication

Problems?

What is IoT?

IoT is like

Canvas

• REST API
• Weather Data
• Avg. Request Size 325b

Data Sample

{
   "deviceId": 231,
   "lat":"45.22838254",
   "lng":"-114.23725403",
   "timestamp":1459509524,
   "temperature":2.99,
   "precipProbability":0.386,
   "humidity":0.055,
   "pressure":1035.617
}

Load Generator

Yandex Tank

Tasks

• Create platform setup
• Gather performance metrics
• Calculate budgets

Plan 1: 86k req/day (1 rps)

Plan 2: 8.64M req/day (100 rps)

Setup: 20$

Response Time

Limitation

Same Setup: 200rps

Why 3 database
servers?

Probability?

Probability of 2 consecutive Heads?

Probability of 3 consecutive Heads?

Servers reliability

Distributed System 
 

High Availability

Any

should consider

Plan 4: 43.2M req/day (500rps)

Setup Variant 1: 380$

Quantiles

Setup Variant 2: 150$

Quantiles

Mircoservices

230 Reasons to choose

Plan 5: 84.6M req/day (1k rps)

Plan 5: 84.6M req/day (1k rps)

Plan 6: 432M req/day (5k rps)

Started to think about bulk inserts?

Plan 7: 1.26B req/day (15k rps)

Quantiles

TCP/IP

TCP Flow

Packets Rate

Packets Rate

Load Balancer Trick

Load Balancer Trick

Load Balancer Trick

Load Balancer Trick

Why?

Load Balancer Trick

Plan 7: 50000 req/sec

Commodity Hardware

Commodity Hardware

$5 Server

1 CPU

20 CPU

c4.8xlarge: $1222.750/monthly

DNS Load Distribution

DNS Load Distribution

DNS Cache

Rule of Thumb: Add LB

What if?

Floating IP

Sharding?

Mysql: Manual Sharding

Mysql: Fabric (pre-alpha)

<?php

$mysqli = new mysqli("myapp", "user", "password", "database");


mysqlnd_ms_fabric_select_shard($mysqli, "test.fabrictest", 10);
$mysqli->query("INSERT INTO fabrictest(id) VALUES (10)");


mysqlnd_ms_fabric_select_shard($mysqli, "test.fabrictest", 10);
$mysqli->query("SELECT id FROM test WHERE id = 10");

http://php.net/manual/ru/mysqlnd-ms.quickstart.mysql_fabric.php

MariaDB: Spider

Mysql Cluster (NDB)

MongoDB Sharding

Apache Cassandra

RabbitMQ

Hits 1 Million Messages Per Second. 32 machines

https://blog.pivotal.io/pivotal/products/rabbitmq-hits-one-million-messages-per-second-on-google-compute-engine

Apache Kafka

2 Million Writes Per Second 3 machines

https://engineering.linkedin.com/kafka/benchmarking-apache-kafka-2-million-writes-second-three-cheap-machines

Instead Summary

• Scalability as afterwords doesn't work
• Database is not a queue
• Database is not a lock system
• Redis is not a queue
• Load balancers as a must
• Linear disk writes wins
• Perfomance in PHP is done by everything except PHP
• Being distributed is freaking hard

Questions?

Find me on

@alexhelkar

alexhelkar

https://github.com/alexhelkar