At the moment I am trying to upload "large" files to a webhosting server. For this I use an input field with multiple='multiple'. Maximum file size is not set for this input field. The PHP version is 7.4. The maximum upload size is set to 256MB by the hoster.

The files are processed by js in a simple loop ( files[ x ] ). The issue is that files larger than 10MB do not get any payload on upload. I generate formdata with file-chunks or full files appended which is only sent when files/chunks are below 10MB or when I let bigger files being sliced via Javascript to chunks under 10MB. The PHP $_FILES- array stays empty on 10MB+ files and the formdata is not available nor shown on upload in chrome/ff dev tools. The requests are sent via jquery $.ajax() after trying fetch and jquery $.POST(). All show the same behaviour. No errors are shown.

By the fact that I can upload 10MB+ files when slicing them to anything under 10MB via javascript slice() and any file below 10MB seems to show me that it is not a script- issue. Files under 10MB work, too when I set the chunk- size to something like 100MB or 200MB which is within the maximum upload size limitation.

Is there any known Apache/nginx server limitation that I might have missed?

Edit 27.05.2022 - 21:00 Here is the code. As you can see it is "nothing too fancy":

    var chunkSize = 100 * 1024 * 1024;
    
    for( var start = 0; start < target.files[ 0 ].size; start +=  chunkSize ){
    var chunk = target.files[ 0 ].slice( start, start + chunkSize );// + 1);
    var fd = new FormData ();
    fd.set( 'data', chunk );
    
await $.ajax({ url : url, type : 'POST', contentType : false, data : fd, cache : false, processData : false
//, dataType : 'formData' 
})

})