PHP PERFORMANCE. Principles and Tools. By Kevin Schroeder Technology Evangelist Zend Technologies. Copyright 2007, Zend Technologies Inc.

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1 PHP PERFORMANCE Principles and Tools By Kevin Schroeder Technology Evangelist Zend Technologies Copyright 2007, Zend Technologies Inc.

2 About me Kevin Schroeder Technology Evangelist for Zend Programmer Sys Admin Author IBM i Programmer s Guide to PHP You want to do WHAT with PHP? Coming up Race Ferraris on the weekend My Honda has a dismal win record

3 If you have a question you can Type in the Q&A panel Tweet #zendperf Follow us! (or search for Zend) (me!)

4 Things we ll look at Database Network Latency IO Contention CPU utilization Network Connectivity Best Practices/Pit Falls/Things to consider

5 Performance Database Tools Zend Server A distinct group of monitoring options for DB s Inter-application query monitoring, usually via a DB adapter abstraction layer Symptoms Pages take a long time to load with Apache/IIS/PHP using proportionally less of the CPU time Causes The list could go on for 1x10 5 slides

6 Performance - Database Possible remedies Simplify your queries Make your queries more complex Tune your database

7 Performance Network Latency Tools Zend Server monitor slow socket function execution Wireshark Tcpdump Symptoms Depends on where the latency is occurring Often slow page responses with low CPU usage Causes Network Saturation (probably not too likely) DNS Reverse Lookups TCP Handshakes High number of hops and much more

8 The TCP handshake T/TCP SYN + Response Data + FIN T/TCP SYN + Response Data + ACK +FIN ACK

9 Hops (not the good kind) Server Client HTTP Layer 7 HTTP Layer 7 UTF-8 Layer 6 TCP Layer 4 Switch/Router UTF-8 Layer 6 TCP Layer 4 IP Layer 3 IP Layer 3 IP Layer 3 IP Layer 3 Ethernet Layer 2 Ethernet Layer 2 Ethernet Layer 2 Ethernet Layer 2 Physical Layer 1 Physical Layer 1 Physical Layer 1 Physical Layer 1

10 Performance IO Contention Tools Zend Server (in extreme cases, long fopen() calls) vmstat & top (Linux) System Internals Process Explorer (Windows) Symptoms Unpredictable and difficult to reproduce page load times Causes Too few spindles serving too much data High write concurrency Insufficient free system RAM

11 Performance CPU Utilization Tools top (Linux) System Internals Process Explorer (Windows) Symptoms Page load times either correspond directly to CPU utilization or are consistently slow Causes Bad code or over-architected solutions Excessive recursion Excessive IO High server utilization too few servers serving too much traffic

12 Performance CPU Utilization There are often 2 different paths this can follow User time Time spent executing the code that you wrote System time Time spent running functionality that your code calls, such as networking, file system, etc.

13 Performance Network Connectivity Tools Zend Server monitor failed calls to socket_connect(), fsockopen() or fread() Wireshark Tcpdump Symptoms Database or web service calls take long to execute If read functions die unexpectedly, bad network hardware might be a cause

14 Choosing the right architecture If you deal with large collections of data, be careful of various ORM techniques or data access methods. This can pertain to the cloud too Limit 100 Limit 500 Limit 1000 Unlimited (250k) Active Record Collection Difference (Col * Dif) = AR

15 OO Beware of magic! get, set, call Situations where they are often used When representing another object that it has no knowledge of - I.e. Soap requests, COM objects, Java objects, database tables When there are property-level permissions on an object s properties. Keeping the properties private and using get/set to determine access If used sparingly they won t affect you, but many modern applications have lots of recursion or large underlying architectures that can have unpredicted consequences

16 !Preg Use preg_match for data checking only when you have to stripos( $website) is over twice as fast as preg_match( / $website) ctype_alnum() is almost 5 times as fast as preg_match( /^\s*$/ ); Casting if ($test == (int)$test) is well over 5 times faster than preg_match( /^\d*$/)

17 Code Acceleration From a test on Wordpress Without acceleration Requests per second: 2.28 Time per request: ms With acceleration Requests per second: 8.11 Time per request: ms 4-fold increase in performance by flipping a (free) switch Zend Server CE is free and has this. You have no excuse!!

18 Do you queue? Offloading long running processes to a queuing system can help make your front end servers scale more vertically Examples include Job Queues Zend Platform/Zend Server 5 Gearman Message Queues ActiveMQ RabbitMQ

19 What not to do This is not complete!!! Oh we ll just cache it Our NFS server is just fine for serving PHP files That LIKE query is necessary You may need to structure your data a little different You might need to use a search engine instead Zend_Search_Lucene SOLR Using arrays is faster than objects, we ll use them instead Monitoring/diagnostic tools are too expensive

20 What TO do This is not complete!!! Minimize require_once calls/use an autoloader Try to make your architecture more horizontal rather than vertical People from Java backgrounds tend to go more vertical Use Lazy Loading/Load on Demand THINK before you code!! Don t just do something because someone else is Use diagnostic tools! Zend Server Monitoring and Code Tracing Zend Studio Profiler (pays for itself if you are 0.5% more productive in a year (according to my calculation)

21 Non-PHP PHP performance rules PHP performance is not the only factor in determining the overall performance of a website. Here are some suggestions Make fewer HTTP requests Use an Expires header Gzip cached content Put stylesheets at the top Put Javascript at the bottom Reduce DNS lookups Avoid redirects

22 Non-PHP PHP performance rules Be aware of your page size Microsoft 238kb 4.4 seconds Oracle 104kb 861ms IBM 640 kb 4.6 seconds Zend 183kb 2.4 seconds There is a fairly direct relationship between the amount of data on your web page and the render time

23 Non-PHP PHP performance rules Similarly, be careful when dealing with lots of Ajax data The browser needs to process that data With large data sets the browser may take a while to update the DOM 2 options Use staggered loading Pass rendered content to the browser and attach with innerhtml

24 Questions?

25 Fin Kevin Schroeder