On 10/07/2015 06:08 PM, Eric Blake wrote:
On 10/07/2015 07:56 AM, Dr. David Alan Gilbert wrote:
* Denis V. Lunev (d...@openvz.org) wrote:
From: Igor Redko <red...@virtuozzo.com>
In this patch the ability to start a migration with test-only
capability was added. It allows to gather the guest VM’s memory
usage statistics avoiding time and memory overheads and real
data transmission. New MIGRATION_STATUS_TEST_COMPLETED was
added to distinguish between test migration and true migration
success states.
Why isn't this just a new transport? i.e. I could do this just by doing
a migrate to test: ?
It seems simpler and avoids some of the special casing?
Indeed. Even if the new state can only be triggered by using a new
option, the fact that the new state exists in introspection means
clients have to figure out what to do with it; while a new transport
would not require any new states ("running" to completion means that
nothing migrated, but the existing states can then be reused to see that
the test: transport has finished computing its numbers).
we need to expose calculated numbers to the caller somehow.
This could be done in MIGRATION_STATUS_COMPLETED state
even for ordinary migration. Will it be OK?
Den
+++ b/qapi-schema.json
@@ -432,6 +432,8 @@
#
# @completed: migration is finished.
#
+# @test-completed: migration time estimation finished.
+#
If this gets added, in spite of our ideas to use a 'test:' transport
instead of a new state, it would need a 'since 2.5' marker.