On Tue, May 5, 2020 at 11:48 PM Chris Murphy <lists@xxxxxxxxxxxxxxxxx> wrote: > > btrfs-progs-5.6-1.fc32.x86_64 > kernel-5.6.8-300.fc32.x86_64 > > I've created a new file system, filled it with ~600G, set the seed > flag, and I'm creating a sprout by adding a 2nd device and removing > the 1st. This used to go at device speeds. Today it's running at > ~35M/s where I expect 95-120M/s. I don't know that it's related to > send/receive performance. Same brand new file system, and a second new file system, doing send/receive with a single snapshot (no other snapshots or subvolumes related to it) and I'm seeing this same abysmal performance. ~5MB/s send. The instant I do 'perf top -g -U' on the send process, the send performance increases 10x to over 50MB/s. As soon as I quit perf top, abysmal performance. Both of these drives scrub at ~100M/s. I'm not sure what's going on or how to get more information but it's a regression. I'll attach a few perf top text files to the next email. -- Chris Murphy
