Outline of what happens when a PHP request is made, how you can measure different aspects of it's execution and improve performance.

1. Anatomy of a PHP
Request
Joseph Scott
15 April 2010
UPHPU

2. Lifespan
.php
Read Parse Compile Execute Output

3. Lifespan
.php
Read Parse Compile Execute Output
Apache / mod_php

4. Lifespan
.php
Read Parse Compile Execute Output
FastCGI
Nginx

5. Reading
Open Read Close

6. Reading
Open Read Close
Avoid co$tly services like NFS

7. Parse
hello.php
<?php
echo "Hello, World!n"
Parse error: syntax error, unexpected $end,
expecting ',' or ';' in /tmp/hello.php on line 3

8. Tokens
<?php echo
$tokens = token_get_all( '
"Hello, World!";' );
foreach ( $tokens as $token ) {
if ( is_array( $token ) ) {
echo token_name( $token[0] ) . " ( {$token[2]} ) -
{$token[1]}n";
} else {
echo "{$token}n";
}
}

9. Tokens
T_OPEN_TAG ( 1 ) - <?php
T_ECHO ( 1 ) - echo
T_WHITESPACE ( 1 ) -
T_CONSTANT_ENCAPSED_STRING ( 1 ) - "Hello,
World!"
;

10. Compile
Branch analysis from position: 0
Return found
filename: /tmp/hello.php
function name: (null)
number of ops: 3
compiled vars: none
line # op fetch ext return operands
-------------------------------------------------------------------------------
2 0 ECHO 'Hello%2C+World%21%0A'
3 1 RETURN 1
2* ZEND_HANDLE_EXCEPTION

11. Execute
Deceptively Simple Term
•Includes all sorts of activity
•Database / remote requests

12. Output
•PHP can buffer output
•Don’t forget about compression

13. Making Things Faster

14. Making Things Faster
.php
Read Parse Compile Execute Output

15. Making Things Faster
.php
Read Parse APC
Compile Execute Output

16. Making Things Faster
.php
Read Parse APC
Compile Execute Output
opcode cache

17. The PHP Point of View
opcodes
VLD - Vulcan Logic Dumper

18. Example PHP
$html = file_get_contents( 'http://www.google.com/' );
$regex_pattern = '!<a href="[^>]*">(.*?)</a>!';
preg_match_all( $regex_pattern, $html, $matches );

19. Example PHP - VLD
Branch analysis from position: 0
Return found
filename: /drive/home/joseph/vld/parse-links.php
function name: (null)
number of ops: 17
compiled vars: !0 = $html, !1 = $regex_pattern, !2 =
$matches

20. Example PHP - VLD
line # op fetch ext return operands
-------------------------------------------------------------------------------
4 0 EXT_STMT
1 EXT_FCALL_BEGIN
2 SEND_VAL 'http%3A%2F%2Fwww.google.com%2F'
3 DO_FCALL 1 'file_get_contents'
4 EXT_FCALL_END
5 ASSIGN !0, $0
5 6 EXT_STMT
7 ASSIGN !1, '%21%3Ca+href%3D%22%5B%5E%3E
%5D%2A%22%3E%28.%2A%3F%29%3C%2Fa%3E%21'
6 8 EXT_STMT
9 EXT_FCALL_BEGIN
10 SEND_VAR !1
11 SEND_VAR !0
12 SEND_REF !2
13 DO_FCALL 3 'preg_match_all'
14 EXT_FCALL_END
7 15 RETURN 1
16* ZEND_HANDLE_EXCEPTION

21. PHP - strace
• System calls, expect LOTS of data
• strace -o out php parse-links.php

22. PHP - strace
• System calls, expect LOTS of data
• strace -o out php parse-links.php
1,786 lines of output!

23. 1.
PHP - strace
socket(PF_INET, SOCK_STREAM, IPPROTO_IP) = 3
2. fcntl64(3, F_GETFL) = 0x2 (flags O_RDWR)
3. fcntl64(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0
4. connect(3, {sa_family=AF_INET, sin_port=htons(80), sin_addr=inet_addr("64.233.169.99")}, 16) =
-1 EINPROGRESS (Operation now in progress)
5. poll([{fd=3, events=POLLIN|POLLOUT|POLLERR|POLLHUP}], 1, 60000) = 1 ([{fd=3,
revents=POLLOUT}])
6. getsockopt(3, SOL_SOCKET, SO_ERROR, [0], [4]) = 0
7. fcntl64(3, F_SETFL, O_RDWR) = 0
8. send(3, "GET / HTTP/1.0rn", 16, MSG_DONTWAIT) = 16
9. send(3, "Host: www.google.comrn", 22, MSG_DONTWAIT) = 22
10.send(3, "rn", 2, MSG_DONTWAIT) = 2
11.poll([{fd=3, events=POLLIN|POLLPRI|POLLERR|POLLHUP}], 1, 0) = 0 (Timeout)
12.poll([{fd=3, events=POLLIN|POLLERR|POLLHUP}], 1, 60000) = 1 ([{fd=3, revents=POLLIN}])
13.recv(3, "HTTP/1.0 200 OKrnDate: Tue, 13 A"..., 8192, MSG_DONTWAIT) = 4636
14.poll([{fd=3, events=POLLIN|POLLERR|POLLHUP}], 1, 60000) = 1 ([{fd=3, revents=POLLIN}])
15.recv(3, "is) class=gb2>Blogs</a> <div cla"..., 8192, MSG_DONTWAIT) = 4290
16.poll([{fd=3, events=POLLIN|POLLERR|POLLHUP}], 1, 60000) = 1 ([{fd=3, revents=POLLIN}])
17.recv(3, "", 8192, MSG_DONTWAIT) = 0
18.poll([{fd=3, events=POLLIN|POLLERR|POLLHUP}], 1, 60000) = 1 ([{fd=3, revents=POLLIN}])
19.recv(3, "", 8192, MSG_DONTWAIT) = 0
20.close(3) = 0

24. Measuring Tape for
Programmers

25. Measuring Tape for
Programmers
Xdebug can provide LOTS of information
http://xdebug.org/

26. Xdebug Profiler
•Generates cachegrind output
➡KCachegrind
➡webgrind
➡MacCallGrind
➡WinCacheGrind
➡Valgrind

27. webgrind

28. Live Demo Time