Scaling PHP Applications with Zend Platform

SCALING PHP APPLICATIONS WITH ZEND PLATFORM

Programming in PHP since the days of 4.2.1

Working for Zend for the last 3½ years

Professional Services, Product Management

If you have a hard time with my name:

German: Shachar

Spanish: Shajar

Russian: Шахар

Arabic: ﺷﺨﺮ

Hebrew: שָחַר

Who am I?

Who are You?

?

Some Introductions:

“ Scaling” ?

Introducing the Zend production stack

Scaling PHP Applications with Zend Platform:

White-box PHP application monitoring: PHP Intelligence

Comprehensive performance features

Parallel execution in PHP: Job Queues

Enabling session scalability: Session Clustering

What are we talking about?

What is “Scalability” ?

“ In telecommunications and software engineering, scalability is a desirable property of a system, a network, or

a process, which indicates its ability

to either handle growing amounts of work in a graceful manner, or to be readily enlarged”

André B. Bondi, 'Characteristics of scalability and their impact on performance'

Scalability means being able to handle the growing traffic...

...but also the growing infrastructure and codebase

Introducing Zend's Production Stack

Zend has some development products:

Zend Studio, Zend Guard,

Zend Framework, PDT

And also some run-time products:

Zend Core

Zend Platform

Zend Engine :-)

...Together, these make the Zend Production Stack

Introducing Zend's Production Stack

Zend Core is Zend's certified and supported distribution of PHP

Zend Platform is Zend's enterprise-grade runtime environment for PHP applications

We think of it as a Web Application Server :

Application-level monitoring

Performance and scalability features

Cluster-wide configuration management

Integrated in a single product, certified, supported

Introducing Zend Platform

PHP Intelligence

Application-level Monitoring

Most monitoring systems concentrate on network, hardware and OS issues

Zend Platform's PHP Intelligence monitors the execution of PHP scripts in your application

A lightweight PHP extension will “listen” for problems like slow executions, errors, and inconsistent memory usage

Alerts are displayed in a central GUI and can trigger predefined actions

Application-level monitoring

Root-cause analysis

When an event is captured, it's context information is also saved

GET, POST, Cookie, function data, backtrace, etc.

This information allows the developer to quickly pinpoint the problem

Integration with Zend Studio allows for instant debugging or profiling

You can instantly reproduce the HTTP request that triggered the problem

Root-cause analysis

PHP Intelligence – Key benefits

Get alerted on PHP issues as they happen throughout your production cluster

Get alerted on problems which are not captured by error logs (slow executions, excess memory consumption, etc.)

Dramatically reduce problem resolution time using instant debugging and root-cause analysis

Allows you to stay on top of the ever-growing codebase complexity

Performance Management

Comprehensive Performance

The performance of a web application can be affected by many different factors, for example:

Network load

PHP processing time

Web server load

Database server load

Application logic – task execution time

Improving the performance of a web application requires a combination of different measures

Comprehensive Performance

Comprehensive Performance Code Acceleration and Optimization

Comprehensive Performance Data Caching API

Using the data caching API

Comprehensive Performance Job Queues

Comprehensive Performance Full-Page Caching

Setting up page caching rules

Comprehensive Performance Output Compression

Comprehensive Performance Client-side Cache Utilization

Comprehensive Performance Zend Download Server

Session Clustering

Session Clustering – The Problem

One of the key issues when scaling out, is sharing session data between cluster nodes

Most load balancers will not provide 100% session affinity

Shared storage tends to become a major bottleneck

NFS: BAD performance, single point of failure

Database: better, but still a bottleneck

Distributes storage is better, but:

Still doesn't provide fail-over persistence

Scaling and managing the storage tends to become difficult

Session Clustering - Example

Session Clustering – Key Benefits

Linear scalability: add more web servers and you are done

Different levels of fail-over persistence:

Non-persistent memory storage

Disk-based storage with delayed write or write-through

High availability mode: Session replication on backup nodes

Easy to set up and manage

Good performance compared to alternative solutions

Transparent to end-users and developers

Job Queues

Job Queue – The Problem

PHP's isolated, shared-nothing architecture does not allow for easy parallel execution

One “job” must finish before the next one is executed

There is no asynchronous execution

Background processing of any kind requires a lot of “hacking”

Job Queues - PHP In a Parallel Universe

Job Queues – Key Features

Jobs are PHP scripts executed in the background

Jobs can be scheduled and managed through either:

An API from within your PHP application

From a centralized web GUI

Allows for elaborate scheduling rules

Provides job failure handling

Provides monitoring and execution statistics

Common Uses: order processing, transaction processing, mail submission, report generation, etc.

Scheduling Jobs – From API or GUI

Job Queues - Example

Benchmark: Offloading e-mail submission Req / Sec # of subscribers Before Job Queue Offloading After Job Queue Offloading A quick benchmark of the changes above shows a dramatic improvement in the application's responsiveness, especially when the amount of subscribers grow.

What Else?