Re: [Qemu-devel] [PATCH 2/4] multifd: Drop x-multifd-page-count parameter

[Laurent Vivier <lvivier@redhat.com>]

On 06/02/2019 18:58, Juan Quintela wrote:
> Laurent Vivier <lvivier@redhat.com> wrote:
>> On 06/02/2019 14:23, Juan Quintela wrote:
>>> Libvirt don't want to expose (and explain it).  And testing looks like
>>> 128 is good for all use cases, so just drop it.
>>>
>>> Signed-off-by: Juan Quintela <quintela@redhat.com>
>>> ---
>>>  hmp.c                 |  7 -------
>>>  migration/migration.c | 30 ------------------------------
>>>  migration/migration.h |  1 -
>>>  migration/ram.c       | 13 ++++++++-----
>>>  qapi/migration.json   | 13 +------------
>>>  5 files changed, 9 insertions(+), 55 deletions(-)
>>>
>> ...
>>> diff --git a/migration/migration.c b/migration/migration.c
>>> index f673486679..65df9b566e 100644
>>> --- a/migration/migration.c
>>> +++ b/migration/migration.c
>>> @@ -81,7 +81,6 @@
>>>  /* The delay time (in ms) between two COLO checkpoints */
>>>  #define DEFAULT_MIGRATE_X_CHECKPOINT_DELAY (200 * 100)
>>>  #define DEFAULT_MIGRATE_MULTIFD_CHANNELS 2
>>> -#define DEFAULT_MIGRATE_MULTIFD_PAGE_COUNT 128
>>
>> Why do you update it in the previous patch to remove it in this one?
> 
> To make clear that I change the default.  Otherwise it gets hidden into
> the whole patch.  if you preffer I could have done the other way around.

OK, I understand. It's not really clear because the new default
(MULTIFD_PAGE_COUNT) is hidden in the patch.

Moreover, in the first patch you update the value, but you don't update
the comments in qapi/migration.json (I've seen that because you remove
them in this patch).

Perhaps you can proceed in the reverse order: remove the parameter and
then set the new default... or merge the two patches and saying in the
commit message you change the default value.

Thanks,
Laurent