Comments on: How does PHP echo’s a “Hello World”? – Behind the scene http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/ PHP, Memcached, XMPP and Web Development Thu, 18 Mar 2010 08:59:29 +0500 http://wordpress.org/?v=2.8.5 hourly 1 By: MySQL Query Cache, WP-Cache, APC, Memcache - What to choose « Abhi’s Weblog http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/comment-page-1/#comment-562 MySQL Query Cache, WP-Cache, APC, Memcache - What to choose « Abhi’s Weblog Wed, 14 Jan 2009 18:19:04 +0000 http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/#comment-562 [...] - An opcode based cache for PHP APC stands for Alternative PHP Cache. In one of my previous post How does PHP echo’s a “Hello World”? - Behind the scene, I talk about how PHP churns out “Hello World” for [...] [...] – An opcode based cache for PHP APC stands for Alternative PHP Cache. In one of my previous post How does PHP echo’s a “Hello World”? – Behind the scene, I talk about how PHP churns out “Hello World” for [...]

]]> By: PHP Extensions - How and Why? | Abhi's Weblog http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/comment-page-1/#comment-427 PHP Extensions - How and Why? | Abhi's Weblog Tue, 09 Dec 2008 15:14:17 +0000 http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/#comment-427 [...] understand what we are going to disucss, I will recommend you to read one of  my previous post How does PHP echo’s a “Hello World”? - Behind the scene . In this post I discussed in brief the backend architecture of [...] [...] understand what we are going to disucss, I will recommend you to read one of  my previous post How does PHP echo’s a “Hello World”? – Behind the scene . In this post I discussed in brief the backend architecture of [...]

]]> By: admin http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/comment-page-1/#comment-426 admin Sat, 29 Nov 2008 09:05:27 +0000 http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/#comment-426 @Rohit Yes i must say PHP is a lot easy to start with. And you can build serious sites faster in PHP than in any other language. But now that I am going through a lot of Python and analyzing the performance, I can find that Python provides a better scalable site. One guy had a 7GB text file that he needed to run some parsing on (to prepare for a DB import). Performance Numbers (on 5 million lines worth of the file) $ time ./split.pl p.test (# Perl 5.8.8) real 0m38.577s user 0m33.554s sys 0m0.848s $ time ./split.py p.test (# Python 2.4.4) real 0m44.895s user 0m42.975s sys 0m0.900s $ time php split.php p.test (# PHP 5.2.6RC4) real 1m10.887s user 0m51.251s sys 0m18.677s which shows PHP is about 50% slower as compared to Perl and Python. Perl is fastest but then Perl is not suitable for web development stuffs. @Rohit
Yes i must say PHP is a lot easy to start with. And you can build serious sites faster in PHP than in any other language.

But now that I am going through a lot of Python and analyzing the performance, I can find that Python provides a better scalable site.

One guy had a 7GB text file that he needed to run some parsing on (to prepare for a DB import). Performance Numbers (on 5 million lines worth of the file)

$ time ./split.pl p.test (# Perl 5.8.8)
real 0m38.577s
user 0m33.554s
sys 0m0.848s

$ time ./split.py p.test (# Python 2.4.4)
real 0m44.895s
user 0m42.975s
sys 0m0.900s

$ time php split.php p.test (# PHP 5.2.6RC4)
real 1m10.887s
user 0m51.251s
sys 0m18.677s

which shows PHP is about 50% slower as compared to Perl and Python. Perl is fastest but then Perl is not suitable for web development stuffs.

]]> By: admin http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/comment-page-1/#comment-425 admin Sat, 29 Nov 2008 08:56:16 +0000 http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/#comment-425 @Piccolo Principe What sort of infinite loop are you talking about? Is it a simple while(1) {} thing that you are referring to? Well I am not sure where did you encountered segmentation fault? Can you give an example of a script you are referring? Once I got an segmentation fault but it wasn't because of a bad script. @Piccolo Principe
What sort of infinite loop are you talking about? Is it a simple while(1) {} thing that you are referring to?

Well I am not sure where did you encountered segmentation fault? Can you give an example of a script you are referring? Once I got an segmentation fault but it wasn’t because of a bad script.

]]> By: Rohit Nair http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/comment-page-1/#comment-424 Rohit Nair Sat, 29 Nov 2008 08:46:59 +0000 http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/#comment-424 Interesting stuff. I guess because PHP is so easy as a language and you have this feeling that "it just works", you tend to overlook its internals and unless you know that, you obviously can't write efficient PHP. Interesting stuff. I guess because PHP is so easy as a language and you have this feeling that “it just works”, you tend to overlook its internals and unless you know that, you obviously can’t write efficient PHP.

]]> By: Piccolo Principe http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/comment-page-1/#comment-423 Piccolo Principe Fri, 28 Nov 2008 16:10:43 +0000 http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/#comment-423 I have seen the case where bad written scripts (infinite recursion) cause php to segfault. What happen in this case? What initialization is repeated? I have seen the case where bad written scripts (infinite recursion) cause php to segfault. What happen in this case? What initialization is repeated?

]]> By: Nikhil Aggarwala http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/comment-page-1/#comment-422 Nikhil Aggarwala Thu, 27 Nov 2008 11:56:00 +0000 http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/#comment-422 Super post. I expect a post on how to write a PHP extension, if you can. I have searched a lot on web and found a lot of so called Hello World PHP extension code. But unfortunately none of them clearly explains each and every piece of that code. From this post I guess you have dealt with PHP extensions and it would be nice if you can share the same with us. @JD001 I am sure that PHP developers must have thought about loading of extensions and surely they must have made it a light weight process. I am sure it won't effect your site performance. Super post. I expect a post on how to write a PHP extension, if you can. I have searched a lot on web and found a lot of so called Hello World PHP extension code. But unfortunately none of them clearly explains each and every piece of that code.

From this post I guess you have dealt with PHP extensions and it would be nice if you can share the same with us.

@JD001
I am sure that PHP developers must have thought about loading of extensions and surely they must have made it a light weight process. I am sure it won’t effect your site performance.

]]> By: JD001 http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/comment-page-1/#comment-421 JD001 Thu, 27 Nov 2008 11:47:20 +0000 http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/#comment-421 Same as Jaisen, I have now concerns over the performance of PHP since its calling RINIT module of each and every extension whether required or not. However thanks for sharing this useful information with us all. Same as Jaisen, I have now concerns over the performance of PHP since its calling RINIT module of each and every extension whether required or not.

However thanks for sharing this useful information with us all.

]]> By: Vitor Almeida da Silva http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/comment-page-1/#comment-420 Vitor Almeida da Silva Thu, 27 Nov 2008 11:41:15 +0000 http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/#comment-420 Interesting post. Thanks for sharing these. Interesting post. Thanks for sharing these.

]]> By: admin http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/comment-page-1/#comment-419 admin Thu, 27 Nov 2008 10:05:24 +0000 http://abhinavsingh.com/blog/2008/11/how-does-php-echos-a-hello-world-behind-the-scene/#comment-419 You got it wrong actually. MINIT is called for each module once only when you start your yapache server. After that only RINIT method is called for each module upon every subsequent page request. RINIT generally involve populating variables e.g. in case of $_SESSION variables, which really doesn't cost much. Even if you are not using it, it will be unset() upon module RSHUTDOWN method call. However its always a better practice to keep an eye on what modules PHP loads by default and what not. In case of high traffic websites that might enhance the performance. (Though I have no stats to show how much enhancement in performance) Note: Step 1 of startup and Step 2 of shutdown, happens when you start and stop SAPI. Step 2 of startup and Step 1 of shutdown happens when a page is requested. You got it wrong actually. MINIT is called for each module once only when you start your yapache server. After that only RINIT method is called for each module upon every subsequent page request.

RINIT generally involve populating variables e.g. in case of $_SESSION variables, which really doesn’t cost much. Even if you are not using it, it will be unset() upon module RSHUTDOWN method call.

However its always a better practice to keep an eye on what modules PHP loads by default and what not. In case of high traffic websites that might enhance the performance. (Though I have no stats to show how much enhancement in performance)

Note: Step 1 of startup and Step 2 of shutdown, happens when you start and stop SAPI. Step 2 of startup and Step 1 of shutdown happens when a page is requested.

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