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References: <20190108194552.45453-1-vsementsov@virtuozzo.com>
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From: Paolo Bonzini <pbonzini@redhat.com>
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Date: Wed, 9 Jan 2019 17:42:51 +0100
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Subject: Re: [Qemu-devel] [PATCH] file-posix: add rough-block-status
 parameter
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To: Kevin Wolf <kwolf@redhat.com>, Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org, armbru@redhat.com, eblake@redhat.com, mreitz@redhat.com, fam@euphon.net, stefanha@redhat.com, den@openvz.org

On 09/01/19 12:23, Kevin Wolf wrote:
> Also note that this is only metadata preallocation; full preallocation
> will still return allocated for the protocol layer and so it will always
> be slow.

Full preallocation these days can create images with preallocated but
known-zero blocks, I think?

Paolo