If it weren't mmaped files, I would use strace/gdb, or even fuse proxy file system. But these are mmaped, I don't know any easy debugging or monitoring solutio

If it weren't mmaped files, I would use strace/gdb, or even fuse proxy file system. But these are mmaped, I don't know any easy debugging or monitoring solution besides writing kprobes/systemtap hooks. How would you debug it?