http://matthewturland.com/2010/05/20/new-spl-features-in-php-5-3/

1. New SPL Features in PHP 5.3
Matthew Turland
CodeWorks '09 Webcast Series
June 26, 2009

2. Salut! Comment sa-va?
●
Senior Consultant at Blue Parabola
● Native of Duson, Louisiana
● Author and TE for php|architect Magazine
● Book coming soon from php|architect
● Contributor to Zend Framework project

3. A Long, Long Time Ago (Or Not)
● Alexander Stepanov
● Conceived of the
STL for C++
●
Goals of SPL are
somewhat similar

4. In a Galaxy Not So Far Away
Pre-5.3 SPL Features
● Classes: ArrayObject, SplFileInfo...
● Interfaces: ArrayAccess, Countable...
● Exceptions: BadFunctionCallException...
● Functions: spl_autoload_register...

5. Oh yeah, and iterators.

6. So What's New?
In comparison to the STL:
● Iterators? Nope.
● Algorithms? Nope.
● Functors? Nope.
● Well, there's only one thing left then...

7. Containers
“A container is a class, a data structure,
or an abstract data type whose instances
are collections of other objects. They are
used to store objects in an organized way
following specific access rules.”
“Container (data structure)” - Wikipedia

8. We Don't Need
No Stinkin' Containers!
array() 'string'

9. Sure We Do! Here's Why...
Scalability!!!

10. Arrays Are Great
● They're a general purpose container.
● This makes them flexible.
● Its underlying algorithm isn't always best.

11. Benchmarks
● Lies, Damned Lies, and Benchmarks - YMMV
● PHP 5.3.0RC4 compiled on Ubuntu 9.04
● Intel Core2Duo 1.83GHz, 4 GB DDR2-RAM

12. Benchmark Runner
#!/bin/bash
# 20 = # executions to perform
# 100 = # elements in the container
# ./bench.sh test.php 20 100
time=`/home/matt/Documents/Projects/php-
5.3.0RC4/build/php_build/bin/php-cgi -q -T $2 $1 $3
2>&1 | tail -n 1 | cut -d " " -f 3`;
avg=`echo "scale=6; $time / $2" | bc`;
echo "$1 $avg";

13. The List

14. SplFixedArray
● Like an array, but with a fixed length.
● Only allows integers >= 0 for keys.
● Can be resized, but at a cost.
● Great for simple enumerated lists.

15. SplFixedArray Code
<?php
$a = array();
for ($i = 0; $i < $argv[1]; $i++) {
$a[$i] = $i;
}
<?php
$a = new SplFixedArray($argv[1]);
for ($i = 0; $i < $argv[1]; $i++) {
$a[$i] = $i;
}

16. SplFixedArray Results
Elements SplFixedArray Array Ratio
10 371 µs 293 µs 1.266
100 501 µs 783 µs 0.640
1,000 899 µs 1,151 µs 0.781
10,000 8,229 µs 9,628 µs 0.855
100,000 49,481 µs 81,028 µs 0.610

17. SplFixedArray Graph
90000
80000
70000
60000
Time (µs)
50000
40000 SplFixedArray
30000 Array
20000
10000
0
10 100 1000 10000 100000
Elements

18. The Stack

19. SplStack
● Last In, First Out (LIFO)
● 2 Operations
● Push - [] for both
● Pop – array_pop() vs ->pop()

20. SplStack Code
<?php
$a = array();
for($i = 0; $i < $argv[1]; $i++) {
$a[] = $i;
}
for($i = 0; $i < $argv[1]; $i++) {
array_pop($a);
}

21. SplStack Code (cont.)
<?php
$a = new SplStack;
for($i = 0; $i < $argv[1]; $i++) {
$a[] = $i;
}
for($i = 0; $i < $argv[1]; $i++) {
$a->pop();
}

22. SplStack Results
Elements SplStack Array Ratio
10 394 µs 311 µs 1.267
100 595 µs 462 µs 1.288
1,000 2,417 µs 2,021 µs 1.196
10,000 15,525 µs 14,296 µs 1.086
100,000 135,854 µs 124,955 µs 1.087

23. SplStack Graph
160000
140000
120000
100000
Time (μs)
80000
SplStack
60000
Array
40000
20000
0
10 100 1000 10000 100000
Elements

24. The Queue

25. SplQueue
● First In, First Out (FIFO)
● 2 Operations
● Enqueue - [] for both
● Dequeue – array_shift() vs ->dequeue()

26. SplQueue Code
<?php
$a = array();
for($i = 0; $i < $argv[1]; $i++) {
$a[] = $i;
}
for($i = 0; $i < $argv[1]; $i++) {
array_shift($a);
}

27. SplQueue Code (cont.)
<?php
$a = new SplQueue;
for($i = 0; $i < $argv[1]; $i++) {
$a[] = $i;
}
for($i = 0; $i < $argv[1]; $i++) {
$a->dequeue();
}

28. SplQueue Results
Elements SplQueue Array Ratio
10 390 µs 347 µs 1.124
100 657 µs 811 µs 0.810
1,000 2,918 µs 14,722 µs 0.198
10,000 17,322 µs 1,440,558 µs 0.012
100,000 137,136 µs 31,413,805 µs 0.004

29. SplQueue Graph
35000000
30000000
25000000
Time (μs)
20000000
15000000
SplQueue
10000000 Array
5000000
0
100 10000
10 1000 100000
Elements

30. The Heap

31. SplHeap, SplMinHeap, SplMaxHeap
● Highest / Lowest First Out
● 2 Operations
● Insert - [] and sort() vs ->insert()
● Remove – array_shift() vs ->extract()

32. SplMinHeap Code
<?php
$a = array();
for($i = 0; $i < $argv[1]; $i++) {
$a[] = rand(1, $argv[1]);
sort($a);
}
for($i = 0; $i < $argv[1]; $i++) {
array_shift($a);
}

33. SplMinHeap Code (cont.)
<?php
$a = new SplMinHeap;
for($i = 0; $i < $argv[1]; $i++) {
$a->insert(rand(1, $argv[1]));
}
for($i = 0; $i < $argv[1]; $i++) {
$a->extract();
}

34. SplMinHeap Results
Elements SplMinHeap Array Ratio
10 516 µs 365 µs 1.414
100 847 µs 2,698 µs 0.314
1,000 4,629 µs 150,179 µs 0.031
10,000 26,459 µs 23,144,131 µs 0.001
100,000 371,613 µs 31,974,805 µs 0.012

35. SplMinHeap Graph
35000000
30000000
25000000
Time (μs)
20000000 SplMinHeap
15000000 Array
10000000
5000000
0
100 10000
10 1000 100000
Elements

36. The Priority Queue

37. SplPriorityQueue
● Operates similarly to a heap
● In fact, uses a heap internally for storage
● Accepts a priority with the element value
● Element with highest priority comes out first

38. SplPriorityQueue Code
<?php
function priority_sort($a,$b) {
return $a[1]-$b[1];
}
$a = array();
$threshold = (int) $argv[1] * 0.1;
for($i = 0; $i < $argv[1]; $i++) {
$a[] = array($i, rand(1,10));
usort($a, 'priority_sort');
if ($i > $threshold) {
array_shift($a);
}
}

39. SplPriorityQueue Code (cont.)
<?php
$threshold = $argv[1] * 0.1;
$a = new SplPriorityQueue;
for($i = 0; $i < $argv[1]; $i++) {
$a->insert($i, rand(1,10));
if ($i > $threshold) {
$a->extract();
}
}

40. SplPriorityQueue Results
Elements SplPriorityQueue Array Ratio
10 369 µs 450 µs 0.820
100 818 µs 4,583 µs 0.178
1,000 6,752 µs 346,094 µs 0.020
10,000 39,308 µs 30,710,530 µs 0.001
100,000 484,752 µs 30,587,806 µs 0.016

41. SplPriorityQueue Graph
35000000
30000000
25000000
Time (μs)
20000000
SplPriorityQueue
15000000
Array
10000000
5000000
0
10 100 1000 10000 100000
Elements

42. By the way, thank this guy
Etienne Kneuss

43. Some Great SPL Resources
●
http://php.net/spl
● http://colder.ch
●
http://blueparabola.com/blog/spl-deserves-some-reiteration
●
http://elizabethmariesmith.com/slides/spl_to_the_rescue.pdf

44. C'est tous!
●
http://ishouldbecoding.com
● http://www.blueparabola.com/blogs/matthew-turland
● matt@ishouldbecoding.com or matthew@blueparabola.com
● Elazar on the Freenode IRC network
● Look for me in Dallas, Atlanta, Miami,
Washington, and New York City
at CodeWorks 2009!
● Watch for my book next quarter!
Source: Christian Flickinger