[RFC PATCH 0/3] qemu: Propagate cluster size to new qcow2 images

Eric Blake eblake at redhat.com
Wed Aug 26 15:32:04 UTC 2020


On 8/26/20 9:56 AM, Peter Krempa wrote:
> Cluster size may have performatnce implications. Propagate the cluster
> size used by the original image to any copy or overlay.
> 
> Peter Krempa (3):
>    qemu: monitor: Detect image cluster size from
>      'query-named-block-nodes'
>    qemu: block: Allow specifying cluster size when using
>      'blockdev-create'
>    qemuBlockStorageSourceCreateDetectSize: Propagate cluster size for
>      'qcow2'

It's not as flexible as allowing the user to customize sizes, but it 
definitely makes sense and is a sane heuristic, better than 
adccidentally creating an overlay with 64k clusters atop a base image 
with 1M clusters.

Series:
Reviewed-by: Eric Blake <eblake at redhat.com>


-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org




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