On Fri, Sep 01, 2023 at 11:06:20AM +0100, Daniel P. Berrangé wrote: > On Fri, Sep 01, 2023 at 11:03:54AM +0100, Richard W.M. Jones wrote: > > I forgot to say that nbdkit is using zlib-ng, since I made the source > > level changes a few weeks back (but most of the nbdkit performance > > improvement comes from being able to use lots of threads). > > Ah that last point is interesting. If we look at nbdkit results we can > see that while zstd is clearly faster, the margin of the win is massively > lower. So I presume we can infer similar margins if qemu-img were > switched too.
FWIW here's the nbdkit commit which added zlib-ng support (assuming you don't want to wait for a compat package). It's not a massive change so something similar might be done for qemu: https://gitlab.com/nbdkit/nbdkit/-/commit/1b67e323e998a5d719f1afe43d5be84e45c6739b Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com libguestfs lets you edit virtual machines. Supports shell scripting, bindings from many languages. http://libguestfs.org
