I had some issues with the file upload module available in the library portlet. I couldn't upload file with a size > 100Mo. I went into the control panel and changed the file upload variable to 1Go (just to test).
Now when i try to upload a file>100MO the following exception is raised in Tomcat:
[UploadServletRequestImpl:101] org.apache.commons.fileupload.FileUploadBase$SizeLimitExceededException:the request was rejected because its size (137465065) exceeds the configured maximum (104857600)
I've tried to set com.liferay.portal.upload.UploadServletRequestImpl.max.size=1048576000 in portal-ext.properties file and classic uploader succeed uploading 136Mb file. However modern uploader failed.
Seems to be a bug in Liferay.