On 16/3/2018 4:58 PM, Alberto Garcia wrote:
On Mon 12 Mar 2018 11:16:57 AM CET, Anton Nefedov wrote:
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -2584,6 +2584,8 @@
#
# @cor_write: a write due to copy-on-read (since 2.11)
#
+# @cluster_alloc_space: an allocation of a cluster
On Mon 12 Mar 2018 11:16:57 AM CET, Anton Nefedov wrote:
> --- a/qapi/block-core.json
> +++ b/qapi/block-core.json
> @@ -2584,6 +2584,8 @@
> #
> # @cor_write: a write due to copy-on-read (since 2.11)
> #
> +# @cluster_alloc_space: an allocation of a cluster file space (since 2.12)
That doesn't
If COW areas of the newly allocated clusters are zeroes on the backing image,
efficient bdrv_write_zeroes(flags=BDRV_REQ_ALLOCATE) can be used on the whole
cluster instead of writing explicit zero buffers later in perform_cow().
iotest 060:
write to the discarded cluster does not trigger COW
