On 23.04.20 17:01, Kevin Wolf wrote:
> The BDRV_REQ_ZERO_WRITE is currently implemented in a way that first the
> image is possibly preallocated and then the zero flag is added to all
> clusters. This means that a copy-on-write operation may be needed when
> writing to these clusters, despite
On 4/23/20 11:04 AM, Kevin Wolf wrote:
Hmm. When we get block status, it is very easy to tell that something reads
as zero when the qcow2 file has the zero bit set, but when the qcow2 file
does not have the zero bit set, we have to then query the format layer
whether it reads as zeros (which
Am 23.04.2020 um 17:36 hat Eric Blake geschrieben:
> On 4/23/20 10:01 AM, Kevin Wolf wrote:
> > The BDRV_REQ_ZERO_WRITE is currently implemented in a way that first the
> > image is possibly preallocated and then the zero flag is added to all
> > clusters. This means that a copy-on-write operation
On 4/23/20 10:01 AM, Kevin Wolf wrote:
The BDRV_REQ_ZERO_WRITE is currently implemented in a way that first the
image is possibly preallocated and then the zero flag is added to all
clusters. This means that a copy-on-write operation may be needed when
writing to these clusters, despite having
The BDRV_REQ_ZERO_WRITE is currently implemented in a way that first the
image is possibly preallocated and then the zero flag is added to all
clusters. This means that a copy-on-write operation may be needed when
writing to these clusters, despite having used preallocation, negating
one of the
