How is PHP memory limit used?

flyingfishfinger

Hi,
Another question. I am running the precaching on a router (i.e small amount of RAM). I have the main PHP.ini set to 32MB (default) and the memory limit for Files Gallery set to 64MB. When I run it, the PHP process eventually takes up 190MB of RAM, then crashes my router.

I asked about this in the forum for my device, they said "The Limit is not the total Memory that can be used, but a Limit for each request." So that begs the question - how do you use the memory limit specified in the Files Gallery config file? I did notice that this only started happening once I had a very large number of files in my image cache directory (60k+), but even before that the process consumed 160MB of RAM - just about ok to not crash the device.

Is there somewhere in the plugin that uses multiple instances for this? I don't mind the precaching task taking a long time (days are fine, as long as it gets through all my images eventually), but I'd prefer it not to crash the router 😃

Thanks,
R

Karl

Files Gallery only uses much memory when resizing images, and the memory required to resize each image, is proportional to the image size. For example, a 5000 x 5000 px image will require much more memory than 190MB to resize, perhaps towards 500MB.

So if you are allowing Files Gallery to exceed the memory limit temporarily, and the server simply is incapable, then it would crash. On normal servers, it's entirely fine to temporarily allow slightly higher memory_limit, because it's entirely within the servers capabilities, and it's not possible to resize images without allocating sufficient memory for the process.
https://www.files.gallery/docs/config/#image_resize_memory_limit

flyingfishfinger

Ok, but if I set the memory-limit in the Files Gallery config to, say, 128MB as you have it by default, how is that intended to behave? You say that's enough to resize images to _6k pixels - how is that measured? Will it refuse to resize anything that needs more than 128MB or do something different?

Karl

flyingfishfinger If you want to find out how much memory is required, there are lots of topics about that on Google "PHP how much memory is required to resize images". It's an approximation. To be honest, I don't quite remember how this happens in the tasks plugin ... This plugin wasn't meant for the public. It would certainly require that you have a sufficiently strong server doing all the processing ... It seems very clumsy to assign a weak server to handle such a massive task, beyond it's capabilities.

flyingfishfinger

That's fair. It SERVES them fine, after resizing. Maybe I could preprocess them on a different machine first?

Karl

flyingfishfinger Maybe I could preprocess them on a different machine first?

That should be possible, but you might need to use a server with the same internal server path structure, because cache names are created based on hashed resource paths.

flyingfishfinger

Yeah, just found that out the hard way. The mount points are different between the machines, so I guess I'll need to do it over again. Oops, but no worries. Learned something!

Karl

flyingfishfinger Unfortunately yes. In the future, I might implement better ways of caching images, for example storing the full path like _files/cache/images/path/to/image.320.jpg. In this case, it would not matter where the resized images were created, and you could even create them manually from another application.