btrfs system slow down with 100GB file

[Richard Shaw]

I'm getting significant iowait while writing to a 100GB file. I have
already made it nocow by copying it to another directory, marking the
director nocow (+C) and using cat <oldfile> <newfile> to re-create it from
scratch.

I was under the impression that this should fix the problem.

On a tangent, it took about 30 minutes to delete the old file... My system
is a Ryzen 5 3600 w/ 16GB or memory but it is a spinning disk. I use an
NVME for the system and the spinning disk for /home.

Currently I'm getting random GUI freezes due to the iowait problem and my
HDD indicator light basically stays on solid for over an hour now.

Any tips?

Thanks,
Richard