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Re: [Xen-devel] [PATCH v3 3/6] libxc/migration: Specification update for CHECKPOINT records

Hi Andrew, David,

  Would you mind if I fix the comments, and combine this series with mine
prepare patches for Remus, and then send it out together?

On 05/12/2015 05:54 PM, David Vrabel wrote:
On 12/05/15 10:35, Andrew Cooper wrote:
Checkpointed streams need to signal the end of a consistent view of VM state,
and the start of the libxl data.
--- a/docs/specs/libxc-migration-stream.pandoc
+++ b/docs/specs/libxc-migration-stream.pandoc
@@ -578,6 +578,23 @@ The verify record contains no fields; its body_length is 0.


+A checkpoint record indicates that the records thusfar in the stream represent

...that all the preceding records in the stream represent...

+a consistent view of VM state.

+     0     1     2     3     4     5     6     7 octet
+    +-------------------------------------------------+
+The checkpoint record contains no fields; its body_length is 0
+A stream containing checkpoint records must have indicated itself as a
+checkpointed stream in the Image Header.  Conversely, a stream not identified
+as checkpointed must not contain checkpoint records.

This paragraph is stale.

I think you should expand a bit more on this record.  Perhaps:

   If the stream is embedded in a higher level toolstack stream, the
   CHECKPOINT record marks the end of the libxc portion of the stream
   and the stream is handed back to the higher level for further

   The higher level stream may then hand the stream back to libxc to
   process another set of records for the next consistent VM state
   snapshot.  This next set of records may be terminated by another
   CHECKPOINT record or an END record.



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