Hi All I am trying to get iowatcher up and running on a VM and I seem to be hitting an issue reading the debugfs trace files. When I run on the VM I continually get messages of the form. This is not specific to iowatcher in that if I run blktrace directly I get something similar: $ blktrace -b 8192 -a queue -a complete -a issue -a notify -o ./trace -D . -d /dev/nvme0n1 <snip> setup_mmap: mmap: Invalid argument Thread 0 failed read of /sys/kernel/debug/block/nvme0n1/trace0: 14/Bad address This is on a generic Ubuntu 22.04 install. $ uname -r 5.15.0-57-generic Now if I run similar commands on an AWS instance things work as expected. AND if I directly pipe the output of blktrace into blkparse it seems to work as expected too, even on the VM. Does anyone have any ideas? Is there a kernel config I am missing that is corrected on the AWS kernel? I assume the fact the NVMe SSD on my VM in emulated via QEMU has no impact on this. BTW this is all because I am working on an updated version of iowatcher that ties into Prometheus so I can track disk access patterns across a fleet of servers [1]. [1]. https://github.com/sbates130272/iowatcher-ng -- Cheers Stephen Bates, PhD.
