Re: [PHP] PHP/Apache: script unexpectedly invoked multiple times in parallel every 30 secs.
Thanks for your contribution Virgil. Unfortunately my file is not index.php (nor anything else declared in a DirectoryIndex directive). I'm planning to fix the issue using a lock to test that the script is not already running before starting it again, but I would like to find out the explanation for this unexpected behavior! Cheers, Marc. On Wed, Mar 11, 2009 at 1:08 PM, Virgilio Quilario < virgilio.quila...@gmail.com> wrote: > > Hi all, > > > > I wrote a PHP script running in Apache which takes more than 30 seconds > to > > complete. It uses set_time_limit() to extend the time it is allowed to > run. > > The script generates thumbnails from a list of images. Upon completion, > the > > script redirects the browser to another page using HTTP headers. > > > > On my local machine (Windows + EasyPHP), the script runs as expected and > > completes after a few minutes. > > > > I observe an unexpected behavior on my production web server: > > - The script runs as expected for the first 30 seconds. > > - After 30 seconds, the same script with the same parameters starts again > in > > a new thread/process. The initial thread/process is *not* interrupted, so > 2 > > threads/processes run in parallel, executing the same sequence of > operations > > with a 30 time shift. > > - The same scenario happens every 30 seconds (i.e.: at 0"30, 1"00, 1"30, > and > > so on), multiplying the parallel threads/processes. > > - The browser keeps on loading while the above happens. > > - After some time, the browser displays a blank page and all the > > threads/processes stop. I assume this is due to resources exhaustion, but > I > > have no means to check this assumption. > > > > I deduced the above reading a text file in which I log the sequence of > > called functions. > > > > Unfortunately I have no access *at all* to my production web server > > configuration (shared hosting, no documentation). I cannot even read the > > configuration settings. While I'm considering moving to another host, I'd > be > > extremely pleased to have an explanation of the observed behavior. > > > > I have browsed the mailing list archives and looked for an explanation in > > other forums to no avail. This thread may deal with the same issue but > does > > not include any explanation or solution: > > http://www.networkedmediatank.com/showthread.php?tid=17140 > > > > Thanks for reading, and please do not hesitate to ask for further > > explanations if what I'm trying to achieve was not clear! > > > > Cheers, > > Marc. > > > > hi Marc, > > probably your php file on your production server is index.php. > and you must have generated a image tag with empty src like below: > > > with src being empty, browsers will load your index.php as if it was > an image url so loading in parallel. > hope this explains your case. > > Virgil > http://www.jampmark.com > Free tips, tutorials, innovative tools and techniques for building and > improving web sites. >
Re: [PHP] PHP/Apache: script unexpectedly invoked multiple times in parallel every 30 secs.
> Hi all, > > I wrote a PHP script running in Apache which takes more than 30 seconds to > complete. It uses set_time_limit() to extend the time it is allowed to run. > The script generates thumbnails from a list of images. Upon completion, the > script redirects the browser to another page using HTTP headers. > > On my local machine (Windows + EasyPHP), the script runs as expected and > completes after a few minutes. > > I observe an unexpected behavior on my production web server: > - The script runs as expected for the first 30 seconds. > - After 30 seconds, the same script with the same parameters starts again in > a new thread/process. The initial thread/process is *not* interrupted, so 2 > threads/processes run in parallel, executing the same sequence of operations > with a 30 time shift. > - The same scenario happens every 30 seconds (i.e.: at 0"30, 1"00, 1"30, and > so on), multiplying the parallel threads/processes. > - The browser keeps on loading while the above happens. > - After some time, the browser displays a blank page and all the > threads/processes stop. I assume this is due to resources exhaustion, but I > have no means to check this assumption. > > I deduced the above reading a text file in which I log the sequence of > called functions. > > Unfortunately I have no access *at all* to my production web server > configuration (shared hosting, no documentation). I cannot even read the > configuration settings. While I'm considering moving to another host, I'd be > extremely pleased to have an explanation of the observed behavior. > > I have browsed the mailing list archives and looked for an explanation in > other forums to no avail. This thread may deal with the same issue but does > not include any explanation or solution: > http://www.networkedmediatank.com/showthread.php?tid=17140 > > Thanks for reading, and please do not hesitate to ask for further > explanations if what I'm trying to achieve was not clear! > > Cheers, > Marc. > hi Marc, probably your php file on your production server is index.php. and you must have generated a image tag with empty src like below: with src being empty, browsers will load your index.php as if it was an image url so loading in parallel. hope this explains your case. Virgil http://www.jampmark.com Free tips, tutorials, innovative tools and techniques for building and improving web sites. -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
[PHP] PHP/Apache: script unexpectedly invoked multiple times in parallel every 30 secs.
Hi all, I wrote a PHP script running in Apache which takes more than 30 seconds to complete. It uses set_time_limit() to extend the time it is allowed to run. The script generates thumbnails from a list of images. Upon completion, the script redirects the browser to another page using HTTP headers. On my local machine (Windows + EasyPHP), the script runs as expected and completes after a few minutes. I observe an unexpected behavior on my production web server: - The script runs as expected for the first 30 seconds. - After 30 seconds, the same script with the same parameters starts again in a new thread/process. The initial thread/process is *not* interrupted, so 2 threads/processes run in parallel, executing the same sequence of operations with a 30 time shift. - The same scenario happens every 30 seconds (i.e.: at 0"30, 1"00, 1"30, and so on), multiplying the parallel threads/processes. - The browser keeps on loading while the above happens. - After some time, the browser displays a blank page and all the threads/processes stop. I assume this is due to resources exhaustion, but I have no means to check this assumption. I deduced the above reading a text file in which I log the sequence of called functions. Unfortunately I have no access *at all* to my production web server configuration (shared hosting, no documentation). I cannot even read the configuration settings. While I'm considering moving to another host, I'd be extremely pleased to have an explanation of the observed behavior. I have browsed the mailing list archives and looked for an explanation in other forums to no avail. This thread may deal with the same issue but does not include any explanation or solution: http://www.networkedmediatank.com/showthread.php?tid=17140 Thanks for reading, and please do not hesitate to ask for further explanations if what I'm trying to achieve was not clear! Cheers, Marc.
