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/1b67e323e998a5d719f1afe43d5be84...
Rich.
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