On Sun, Feb 05, 2023 at 04:35:41PM +0000, Richard W.M. Jones wrote: > I'm still adding instrumentation to see if the theory above is right, > plus I have no idea how to fix this.
Turns out I didn't need to add instrumentation. Simply forcing nbdcopy to use at most 1 request per connection (-R 1) recovers all the performance. $ time ./nbdkit -r -U - curl file:/var/tmp/big --run 'nbdcopy --no-extents -R 1 -p "$uri" null:' I still have no good idea how to solve this. Somehow I had to adjust the libcurl handle pool so that it isn't first-come first-served, but prefers to spread available handles across connections. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-builder quickly builds VMs from scratch http://libguestfs.org/virt-builder.1.html _______________________________________________ Libguestfs mailing list Libguestfs@redhat.com https://listman.redhat.com/mailman/listinfo/libguestfs
