Welcome!

Related Topics: @BigDataExpo, Java IoT, Linux Containers, PHP, Agile Computing, @CloudExpo

@BigDataExpo: Article

How to Spruce Up Your Evolved PHP Application

Three performance improvement steps

Do you have a PHP application running and have to deal with inconveniences like lack of scalability, complexity of debugging, and low performance? That's bad enough! But trust me: you are not alone.

I've been developing Spelix, a system for cave management, for more than 20 years. It originated from a single user DOS application, and has now emerged into a web application with hundreds of users, used nationwide as the official cave directory in Austria.

Just as many software projects: Spelix evolved from MS DOS to PHP-powered Web 2.0 with increased demand for functionality and scalability

Recently I applied for a job at Compuware. For a presentation during my job interview I prepared a case study about how to monitor and improve performance of Spelix with dynaTrace, a tool in Compuware APM's suite. I found more hotspots than expected, and it was much easier than expected to resolve them. I also killed two birds with one stone: Spelix is really performing now and I've got a cool, new job.

Let me share with you my experiences in that process and the best practices I've applied to bring spelix.at to its current stage.

The Challenge of Software Evolution
When we start to design a new application we have the chance to consider data volume, number of users, traffic, all of these thoughts that drive us in selecting the proper architecture. But not many of us are able to follow that procedure, because we have to deal with a grown application. A system has emerged from a tiny set of tools and scripts, more and more functionality has been added over the years. Optimization processes often concentrate on the PHP core app to create performing database access, processing and content rendering, but that's not enough. Unfortunately other tiers are not included in these processes. Too often on the client side, the brush-up ends after designing a new frontend, using existing JavaScript plugins, and not thinking about application performance. But a slow database or browser code can dramatically slow down your application, even with an optimized PHP core.

In Spelix I have identified six major scopes for performance optimization:

  1. Database
  2. Server Side Data Caching
  3. Client Side Data Caching
  4. Network Traffic
  5. Browser / CDN Cache
  6. Server Side Session Handling

To be more digestible, this blog is split into two. This post focuses on the first three performance improvement steps and the next one focuses on the last three.

Step #1: Optimize Database Access
In the early stages of an application, it may not be relevant how your database access is designed. As long as the amount of data is low, a poorly designed query or missing indexes may not really affect overall response times. Therefore, database performance is rarely a topic that comes up in many cases. Once it has become an issue, it may be rather complicated to be handled. It's important to place enough value in your database design right from the start. Here are some of my lessons learned and best practices:

Interaction of Views & Indexes
I don't want to get into too much detail about creating indexes as many other articles have covered this. But it's rather important to understand when an index is not used: be careful when using views in MySQL!

When should you use views? Views are perfect to create complex queries and store them for further use. Views are commonly used to prepare data for presentation, or even for data pre-selection based on user access rights.

When should you avoid views? While a WHERE clause on a simple view may cause an index to be used, this could fail in complex view, even though the WHERE clause is on the primary key for the primary table. Once your query gets too complex, MySQL creates a temporary table for the result of the view, and then applies the query on top of the view, without any indexes to be used. Be alert when your view contains commands like GROUP_BY, ORDER_BY, or UNION. So what? My key advice on this is: when you create a view, define possible WHERE clauses and check the execution plan in the database by using the EXPLAIN command. If your WHERE clause is on a column in a table marked as select type "primary", you are on the save side to use the view. If it's "derived" or "dependent subquery", your query might not use existing indexes. It could be better to execute the query code from the application. If you have executed the SQL statements directly from your business logic, create a data access layer that contains your query code. Consider executing multiple SQL statements and merge the data in your PHP code rather than using complex joins that may spoil your indexes.

Check and Eliminate Redundant Statements
Check if your SQL executions are really necessary! You might have executed your statement in an earlier stage, is there really a requirement to run it again? Would it make sense to keep the data in your current context instead of re-requesting it? The following screenshot shows the database statements executed by the PHP Application.

A very good metric is "Executions per calling Transaction" which makes it easy to highlight statements, which are called several times, maybe too often per transaction. If that number is greater than 1, you might want to dig deeper into your code and try to optimize that. In this example "select * from sys2" reads the settings for the current user, which is not going to change permanently. There is no requirement to run this query redundantly.

What to look for? Find your query invocations in your code and avoid repetitive executions.

Optimizations? Depending on the type of information, consider caching your data in your transaction, session storage or overall server side cache, as described in the next section.

Seeing the actual SQL Statements in the context of the request makes it easier to optimize executions of database queries.

For steps 2 and 3, and for further insight, click here for the full article.

More Stories By Harald Zeitlhofer

Harald Zeitlhofer has 15+ years of experience as an architect and developer of enterprise ERP solutions and web applications with a main focus on efficient and performant business processes, usability and application design. As a Technology Strategist in Dynatrace's Centre of Excellence team he influences the Dynatrace product strategy by working closely with customers and driving their performance management and improvement at the front line. He is a frequent speaker at conferences and meetup groups around the world. Follow him @HZeitlhofer

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Latest Stories
One of the bewildering things about DevOps is integrating the massive toolchain including the dozens of new tools that seem to crop up every year. Part of DevOps is Continuous Delivery and having a complex toolchain can add additional integration and setup to your developer environment. In his session at @DevOpsSummit at 18th Cloud Expo, Miko Matsumura, Chief Marketing Officer of Gradle Inc., will discuss which tools to use in a developer stack, how to provision the toolchain to minimize onboa...
Data-as-a-Service is the complete package for the transformation of raw data into meaningful data assets and the delivery of those data assets. In her session at 18th Cloud Expo, Lakshmi Randall, an industry expert, analyst and strategist, will address: What is DaaS (Data-as-a-Service)? Challenges addressed by DaaS Vendors that are enabling DaaS Architecture options for DaaS
DevOps is not just last year’s buzzword. Companies with DevOps practices are 2.5x more likely to exceed profitability, market share, and productivity goals. But how do you enable high performance? What can you do right now to start? Find out from DevOps experts including Gene Kim, co-author of "The Phoenix Project," and the Dynatrace Center of Excellence.
SYS-CON Events announced today that Avere Systems, a leading provider of enterprise storage for the hybrid cloud, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. Avere delivers a more modern architectural approach to storage that doesn’t require the overprovisioning of storage capacity to achieve performance, overspending on expensive storage media for inactive data or the overbuilding of data centers ...
Sensors and effectors of IoT are solving problems in new ways, but small businesses have been slow to join the quantified world. They’ll need information from IoT using applications as varied as the businesses themselves. In his session at @ThingsExpo, Roger Meike, Distinguished Engineer, Director of Technology Innovation at Intuit, showed how IoT manufacturers can use open standards, public APIs and custom apps to enable the Quantified Small Business. He used a Raspberry Pi to connect sensors...
SYS-CON Events announced today that Catchpoint Systems, Inc., a provider of innovative web and infrastructure monitoring solutions, has been named “Silver Sponsor” of SYS-CON's DevOps Summit at 18th Cloud Expo New York, which will take place June 7-9, 2016, at the Javits Center in New York City, NY. Catchpoint is a leading Digital Performance Analytics company that provides unparalleled insight into customer-critical services to help consistently deliver an amazing customer experience. Designed...
With the proliferation of both SQL and NoSQL databases, organizations can now target specific fit-for-purpose database tools for their different application needs regarding scalability, ease of use, ACID support, etc. Platform as a Service offerings make this even easier now, enabling developers to roll out their own database infrastructure in minutes with minimal management overhead. However, this same amount of flexibility also comes with the challenges of picking the right tool, on the right ...
SYS-CON Events announced today that Alert Logic, Inc., the leading provider of Security-as-a-Service solutions for the cloud, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. Alert Logic, Inc., provides Security-as-a-Service for on-premises, cloud, and hybrid infrastructures, delivering deep security insight and continuous protection for customers at a lower cost than traditional security solutions. Ful...
SYS-CON Events announced today that Interoute, owner-operator of one of Europe's largest networks and a global cloud services platform, has been named “Bronze Sponsor” of SYS-CON's 18th Cloud Expo, which will take place on June 7-9, 2015 at the Javits Center in New York, New York. Interoute is the owner-operator of one of Europe's largest networks and a global cloud services platform which encompasses 12 data centers, 14 virtual data centers and 31 colocation centers, with connections to 195 ad...
Recognizing the need to identify and validate information security professionals’ competency in securing cloud services, the two leading membership organizations focused on cloud and information security, the Cloud Security Alliance (CSA) and (ISC)^2, joined together to develop an international cloud security credential that reflects the most current and comprehensive best practices for securing and optimizing cloud computing environments.
Companies can harness IoT and predictive analytics to sustain business continuity; predict and manage site performance during emergencies; minimize expensive reactive maintenance; and forecast equipment and maintenance budgets and expenditures. Providing cost-effective, uninterrupted service is challenging, particularly for organizations with geographically dispersed operations.
SYS-CON Events announced today that Commvault, a global leader in enterprise data protection and information management, has been named “Bronze Sponsor” of SYS-CON's 18th International Cloud Expo, which will take place on June 7–9, 2016, at the Javits Center in New York City, NY, and the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Commvault is a leading provider of data protection and information management...
SYS-CON Events announced today that VAI, a leading ERP software provider, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. VAI (Vormittag Associates, Inc.) is a leading independent mid-market ERP software developer renowned for its flexible solutions and ability to automate critical business functions for the distribution, manufacturing, specialty retail and service sectors. An IBM Premier Business Part...
With an estimated 50 billion devices connected to the Internet by 2020, several industries will begin to expand their capabilities for retaining end point data at the edge to better utilize the range of data types and sheer volume of M2M data generated by the Internet of Things. In his session at @ThingsExpo, Don DeLoach, CEO and President of Infobright, will discuss the infrastructures businesses will need to implement to handle this explosion of data by providing specific use cases for filte...
In most cases, it is convenient to have some human interaction with a web (micro-)service, no matter how small it is. A traditional approach would be to create an HTTP interface, where user requests will be dispatched and HTML/CSS pages must be served. This approach is indeed very traditional for a web site, but not really convenient for a web service, which is not intended to be good looking, 24x7 up and running and UX-optimized. Instead, talking to a web service in a chat-bot mode would be muc...