Disk partition /var/asmdata1 has less than 30% free

I'd also like to know how we can cleanup /var/asmdata1. I've received the warning that "The disk partition free space is very limited". I've deleted the requests in the GUI. It only contains a few records now, on the filesystem however, I still have months of request_logs. Last access time is long ago so these files are not being used apparently but I'm still hesitant to delete them. I don't want to corrupt any database index records etc. I cannot find information about this anywhere.

kind regards Matthias