Now before anyone tries consider this question a duplicate, I'd like to say that I've looked at all the similar questions on SO and other forums to absolutely no avail. I tried all the solutions posted and nothing worked. With that being said, here's the problem:
I have a large set of jpg/jpeg images (6000-20000), each of maximum 10 KB in size, each of dimensions 512x512 pixels, being uploaded on my Azure web + MySQL setup. I figured out how to upload that many files without breaking the code or our service and everything is cool.
What I do with these images once they are uploaded is that I build a tiling pyramid of sorts. If there are 5000 images, I tile 'em together in batches of 4 images at a time to form a single image, resample the resultant image using PHP to half its size, and store it as a new tile in a folder representing another level in this pyramid. Hence if all the base files (that were uploaded) are stored in Folder-1 then the new images being created are stored in Folder-2, then Folder-3, and so on until there aren't any images left to tile. At this point all the images have been stitched together and sampled down to 1 image. Now for those of you familiar with deep zoom concepts on the web, you would understand why this is necessary.
Now, here's the real problem. All of this works perfectly well on localhost. I ported this code to a personal server of mine which is CentOS running LAMP and it worked perfectly fine. However, on the company server which is a free tier Azure Web + MySQL instance, the process return an internal server error.
To be more specific, this pyramid functionality is invoked by jQuery AJAX once the upload function returns a success. As part of the process on PHP, I move the uploaded PHP files from the designated temporary location to its actual upload location and begin processing the images for tiling. Usually, the entire pyramid generation takes between 5-15 minutes depending on the number of base images I uploaded. These statistics are based on how it worked on a localhost. On the server, I'm hitting some sort of a limit or a timeout that seems to be killing my PHP after a few minutes. The images stop being processed after maybe two levels of creation. This process works well when the total images are less than 2000.
Sometimes, the AJAX fails. But, when I check the uploads folder via Filezilla, the images continue being processed since I see them being created by my script. At this point if my script doesn't complete in an unknown bit of time, it dies too. I arrived at this conclusion with the fact that no more images/folders for subsequent processing were being created.
Before you say it, my PHP.ini settings have been modified and I've restarted the server countless times before posting here. These are my current settings:
max_execution_time = 9999
memory_limit = 3G
post_max_size = 10G
upload_max_filesize = 1G
max_input_time = 9999
phpinfo() reflects this, too. .htaccess has no role here so trying it made no difference. It wasn't recognized. web.config seems to work and I've also added the line to it:
<system.web>
<httpRuntime executionTimeout="9999" maxRequestLength="2097151"/>
</system.web>
This makes no difference, too. I know the web.config file works because I tried to play around with other settings in it and the changes do reflect in the web app.
So, what is it that I'm missing? I tried raising a support ticket but Azure doesn't let me don that unless I'm on the paid package. I can post my code if required but I'm quite certain that it isn't necessary since it works perfectly well on my localhost and on my personal Linux server.
I've spent way too much time on this problem. Any help would be appreciated. Thanks in advance!
