This is episode 4 of the building the perfect PHP app for the enterprise webinar series. Nothing is faster than a frustrated user clicking away from your site or abandoning your service. Avoid attrition by learning how to tune your applications towards lightning-fast page loads and response times. Learn: the basic principles behind enterprise PHP performance management; How to optimize workloads through background jobs and caching; How to measure performance and make data-driven decisions.

1. Building the perfect PHP app for the enterprise
Episode 4: Optimizing
performance
Zeev Suraski
Twitter: @zeevs
Email: zeev@zend.com

2. 2
Series overview
Keeping up with PHP
Developing apps faster
Resolving problems and high availability
Now: Optimizing performance ←

3. Zeev Suraski
CTO, Zend
Rogue Wave Software

4. 4
• 3 daughters
• Photography enthusiast
• Crazy about spicy foods
• Programming since the age of 12
• Last thing I did before getting involved with PHP
was C++ CGIs (no!)
About me

5. 5
Enterprise PHP is mission-critical
• Built securely
• Delivers optimal performance + scale
• Always on
• Meets release timelines
• Modernizes legacy business logic
• Clear support path (production + LTS)

6. 6
What is performance?
The effectiveness of a computer
system, as measured by agreed-
upon criteria, such as throughput,
response time and availability.

7. 7
Performance is important
• F1000: Average annual cost of
application downtime per hour
$500K – $1M
• F1000: Average time to restore
an application failure
80% > 1 hour
25% > 12 hours
• F1000: Average annual cost of
application downtime
$125M - $250M
A 1 second delay in page response can result
in a 7% reduction in conversion.
IDC, “DevOps and the Cost of Downtime:
Fortune 1000 Best Practice Metrics Quantified”
Akamai research

8. 8
What influences performance?
Almost Anything!
• Hardware (virtual/real)
• Network bandwidth
• Application complexity
• Memory consumption
• Response time of databases and service providers
• User/client load
• Time (of day, day of week, holidays, etc.)

9. Measuring & improving
performance

10. 10
Performance isn’t a one-off process
Develop
Measure
Optimize
Monitor

11. 11

12. Develop

13. 13
Performance during development
• Three Rules of Code Optimization:
1. Don’t.
2. Don’t yet.
3. Profile first.
• Design for performance
• Pay attention to performance as you develop,
but don’t optimize prematurely

14. 14
Additional tools
• IDE – PhpStorm, Zend Studio
• Code Tracing
• xhprof

15. Measure

16. 16
Measuring performance

17. 17
Measuring performance - It’s hard…
It’s dangerously easy to get results.
It’s remarkably difficult to get accurate results.
Challenges:
• Simulating real-world workloads
• Locking issues
• Hardware changes
• Underlying software changes
• Infrastructure fluctuations (software, hardware, network)
• Uncertainty principle

18. 18
Measuring performance – How?
Common measurements:
• Requests per second (req/s)
• Response time
• Latency
Software:
Siege

19. 19
Measuring performance - Tips
• Automate
• Use repeatable hardware
• Dedicated hardware
• Documented cloud/virtual instances
• Perform a ‘warmup’
• Look for cron jobs
• Simulate realistic scenarios
• Use separate load generating machines
• Must also be repeatable
• Have expectations & validate them
• If results are completely off, research why
• Conduct each individual benchmark at least 3 times
• Perform often
• Automate

20. Optimize

21. 21
Web erver
PHP
Frameworks
Apps
App server services

22. Load balancer
End users
Database
Web server
PHP
Frameworks
Apps
App server services
Web server
PHP
Frameworks
Apps
App server services
Web server
PHP
Frameworks
Apps
App server services
Service
backends

23. Load balancer
End users
Database
Web server
PHP
Frameworks
Apps
App server services
Web server
PHP
Frameworks
Apps
App server services
Web server
PHP
Frameworks
Apps
App server services
Service
backends

24. 24
Under The Hood

25. 25
Opcode Caching
Zend
OPcache

26. 26
Opcode caching
OPcache
• Turnkey
Requires absolutely no changes to your code
• Very substantial performance yields
Usually at least 2x better performance
• Free & integrated into PHP
Zend’s OPcache (formerly Optimizer+) donated to the community in 2012
• Very modest requirements
Typically requires only several dozen to a few hundred megabytes of
memory server-wide
• Verdict: Always use

27. Web server
PHP
Frameworks
Apps
App server services
End users
Database
Service
backends
Web server
PHP
Frameworks
Apps
App server services
Web server
PHP
Frameworks
Apps
App server services
Load balancer

28. 28
PHP 7 – The fastest PHP ever

29. 29
PHP 7 – The fastest PHP ever
PHP 5 PHP 7
72
56
72
32
24
16
Hash Table Bucket zVal
PHP 5 PHP 7
20%
5%
Memory Manager CPU Overhead (WP)Memory Consumption of key Data Structures
(bytes)

30. 30
Web server
PHP
Frameworks
Apps
App server services
End Users
Database
Service
Backends
Web server
PHP
Frameworks
Apps
App server services
Web server
PHP
Frameworks
Apps
App server services
Load balancer

31. 31
Web server software and setup
Different Web Server software have different
performance characteristics. Some are faster than
others.
Pay attention to:
• Apache vs. Nginx vs. IIS
• mod_php vs. FPM
• Concurrency settings
• KeepAlive settings

32. 32
End Users
Database
Service
Backends
Web server
PHP
Frameworks
Apps
App server services
Web server
PHP
Frameworks
Apps
App server services
Web server
PHP
Frameworks
Apps
App server services
Load balancer

33. 33
Data caching
Save expensive ops, such as database queries, API calls,
filesystem access, etc. by caching and reusing results.
• Pros:
• Eliminates (or greatly reduces) time of costly calls
• Reduces load on the database, service provider, filesystem
• Time spent fetching from cache typically around zero
• Cons:
• Requires code modifications
• Only works if results don’t change for long periods of time (typically >10
seconds)
• Verdict: Greatly improves performance when used in the right places.

34. End users
Database
Service
backends
Web server
PHP
Frameworks
Apps
App server services
Web server
PHP
Frameworks
Apps
App server services
Web server
PHP
Frameworks
Apps
App server services
Load balancer

35. 35
Page caching
Eliminates the entire execution time of the page by caching
its entire content.
• Pros:
• Page execution time is reduced to zero
• Saves memory, resources, database and CPU load
• Cons:
• Only suitable in situations where an entire rendered page can be
repeatedly served more than once for long periods of time.
• Requires configuration
• Verdict: By far the best performance booster, use whenever possible.

36. 36
What is performance?
The effectiveness of a computer
system, as measured by agreed-
upon criteria, such as throughput,
response time and availability.

37. 37
Perceived performance
How quickly software appears
to perform its task.

38. Load balancer
End users
Database
Service
backends
Web server
PHP
Frameworks
Apps
App server services
Web server
PHP
Frameworks
Apps
App server services
Web server
PHP
Frameworks
Apps
App server services

39. 39
Asynchronous processing
Perform long-running tasks asynchronously.
In other words, instead of waiting for them to
complete, perform them in the background and
notify the user once they’re done (if necessary)
• Pros:
• Radically improve perceived performance for use cases such as credit
card clearance, PDF generation, sending email
• Distribute load among servers
• Cons:
• Requires code changes
• Only suitable for specific use cases

40. Monitor

41. 41
Monitoring
Monitoring is important:
• Things change when the rubber meets the road
• Enables SLA between ops & business owners
• Finger on the pulse
• Find performance issues that would otherwise go
unnoticed (by you, not your customer)

42. 42
Recap
• Performance is important to your business
• Performance is a cycle, not a one-off investment
• Set expectations – both with yourself and your business owners
• Tools can greatly help
• Especially if they’re baked into your dev cycle

43. 43
Learn more
• Watch this webinar on demand
• Read the recap blog

44. Thank you!