[PHP] Odd performance problem
Hello, While debugging a script that ran too slowly I came across something that I can't explain. It is inactive code that when removed doubles the run time of the script. Specifically, the issue is a switch statement, where one of the cases is never reached. If I remove the case from the code, the run time of the script goes from 6 seconds to 12 seconds. To see this problem in action, you can download the problematic script here: http://sebrechts.net/files/2008/phpperfissue.zip Anyone have any ideas on how this is even possible? I'd like to improve the run time of the script, but if every part of code that I take out makes it run longer ... Thanks -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Odd performance problem
On Wed, 2008-05-07 at 17:31 +0200, Joeri Sebrechts wrote: Hello, While debugging a script that ran too slowly I came across something that I can't explain. It is inactive code that when removed doubles the run time of the script. Specifically, the issue is a switch statement, where one of the cases is never reached. If I remove the case from the code, the run time of the script goes from 6 seconds to 12 seconds. To see this problem in action, you can download the problematic script here: http://sebrechts.net/files/2008/phpperfissue.zip Anyone have any ideas on how this is even possible? I'd like to improve the run time of the script, but if every part of code that I take out makes it run longer ... Runs the same for me either way... under PHP4 and PHP5. You must have a nice system, takes 22 seconds both ways on my Athlon 2400 :) Cheers, Rob. -- http://www.interjinn.com Application and Templating Framework for PHP -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
RES: [PHP] Odd performance problem
My tests on PHP 4.4.8 Default files: Run 1) done at 100045 Time: 12.5804 Seconds Run 2) done at 100045 Time: 12.6775 Seconds Run 3) done at 100045 Time: 13.0696 Seconds Now editing the file, removed the switch case 'a' part. Run 1) done at 100045 Time: 12.6981 Seconds Run 2) done at 100045 Time: 12.8659 Seconds Run 3) done at 100045 Time: 12.7886 Seconds As you can see, there's no really big difference here. It really does look like it's slower, but .1 sec slower. Hey Robert, this was just a semprom 3k... didn't know they were that dif Thiago Henrique Pojda Desenvolvimento Web +55 41 3033-7676 [EMAIL PROTECTED] Excelência em Softwares Financeiros -Mensagem original- De: Robert Cummings [mailto:[EMAIL PROTECTED] Enviada em: sexta-feira, 9 de maio de 2008 04:44 Para: Joeri Sebrechts Cc: php-general@lists.php.net Assunto: Re: [PHP] Odd performance problem On Wed, 2008-05-07 at 17:31 +0200, Joeri Sebrechts wrote: Hello, While debugging a script that ran too slowly I came across something that I can't explain. It is inactive code that when removed doubles the run time of the script. Specifically, the issue is a switch statement, where one of the cases is never reached. If I remove the case from the code, the run time of the script goes from 6 seconds to 12 seconds. To see this problem in action, you can download the problematic script here: http://sebrechts.net/files/2008/phpperfissue.zip Anyone have any ideas on how this is even possible? I'd like to improve the run time of the script, but if every part of code that I take out makes it run longer ... Runs the same for me either way... under PHP4 and PHP5. You must have a nice system, takes 22 seconds both ways on my Athlon 2400 :) Cheers, Rob. -- http://www.interjinn.com Application and Templating Framework for PHP -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Odd performance problem
Ha, I tried again today, and now there's no difference. I'm thinking now that this was some sort of page boundary issue, or something of the sort. On the one hand it's a relief I can move on, on the other hand it's frustrating because I know for a fact that I saw those differences, and this problem might be happening for some of our customers. I'll just blame windows, that always works :) By the way, a 22 second run-time is definitely abnormal. I only have a 3 ghz P4, a 3 year old machine. When I disable xdebug it takes 4.5 seconds. Another by the way, while measuring the performance of this script I noticed that wincachegrind's time reports are incorrect. It reported a cumulative run-time of about one second. Kcachegrind (the KDE4 for windows version) did report correct times, so I'll be using that from now on. Thiago Pojda [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] My tests on PHP 4.4.8 Default files: Run 1) done at 100045 Time: 12.5804 Seconds Run 2) done at 100045 Time: 12.6775 Seconds Run 3) done at 100045 Time: 13.0696 Seconds Now editing the file, removed the switch case 'a' part. Run 1) done at 100045 Time: 12.6981 Seconds Run 2) done at 100045 Time: 12.8659 Seconds Run 3) done at 100045 Time: 12.7886 Seconds As you can see, there's no really big difference here. It really does look like it's slower, but .1 sec slower. Hey Robert, this was just a semprom 3k... didn't know they were that dif Thiago Henrique Pojda Desenvolvimento Web +55 41 3033-7676 [EMAIL PROTECTED] Excelência em Softwares Financeiros -Mensagem original- De: Robert Cummings [mailto:[EMAIL PROTECTED] Enviada em: sexta-feira, 9 de maio de 2008 04:44 Para: Joeri Sebrechts Cc: php-general@lists.php.net Assunto: Re: [PHP] Odd performance problem On Wed, 2008-05-07 at 17:31 +0200, Joeri Sebrechts wrote: Hello, While debugging a script that ran too slowly I came across something that I can't explain. It is inactive code that when removed doubles the run time of the script. Specifically, the issue is a switch statement, where one of the cases is never reached. If I remove the case from the code, the run time of the script goes from 6 seconds to 12 seconds. To see this problem in action, you can download the problematic script here: http://sebrechts.net/files/2008/phpperfissue.zip Anyone have any ideas on how this is even possible? I'd like to improve the run time of the script, but if every part of code that I take out makes it run longer ... Runs the same for me either way... under PHP4 and PHP5. You must have a nice system, takes 22 seconds both ways on my Athlon 2400 :) Cheers, Rob. -- http://www.interjinn.com Application and Templating Framework for PHP -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: RES: [PHP] Odd performance problem
On Fri, 2008-05-09 at 08:42 -0300, Thiago Pojda wrote: Runs the same for me either way... under PHP4 and PHP5. You must have a nice system, takes 22 seconds both ways on my Athlon 2400 :) Maybe it's because I use Evolution for my mail client and it has steadily increased it's CPU suckage over the years. I have no idea what it does but these days I noticed it's eating a steady 8-12% of my CPU :( Unfortunately I didn't like Thunderbird last time I checked. Maybe I'll give Opera's mail client a go since I use the Opera browser anyways. Cheers, Rob. -- http://www.interjinn.com Application and Templating Framework for PHP -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
