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.quilario@xxxxxxxxx> 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: > <img src=""> > > 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. >