Re: [PATCH qemu 2/2] dump: Only use the makedumpfile flattened format when necessary

[Stephen Brennan]

Marc-André Lureau <marcandre.lureau@gmail.com> writes:

> Hi
>
> On Wed, Aug 23, 2023 at 2:03 PM Marc-André Lureau
> <marcandre.lureau@gmail.com> wrote:
>>
>> Hi
>>
>> On Wed, Aug 23, 2023 at 4:31 AM Stephen Brennan
>> <stephen.s.brennan@oracle.com> wrote:
>> >
>> > Stephen Brennan <stephen.s.brennan@oracle.com> writes:
>> > > Marc-André Lureau <marcandre.lureau@gmail.com> writes:
>> > >> I am a bit reluctant to change the dump format by default. But since the
>> > >> flatten format is more "complicated" than the "normal" format, perhaps 
>> > >> we
>> > >> can assume all users will handle it.
>> > >>
>> > >> The change is probably late for 8.1 though..
>> > >
>> > > Thank you for your review and testing!
>> > >
>> > > I totally understand the concern about making the change by default. I
>> > > do believe that nobody should notice too much because the normal format
>> > > should be easier to work with, and more broadly compatible. I don't know
>> > > of any tool which deals with the flattened format that can't handle the
>> > > normal format, except for "makedumpfile -R" itself.
>> > >
>> > > If it's a blocker, I can go ahead and add a new flag to the command to
>> > > enable the behavior. However there are a few good justifications not to
>> > > add a new flag. I think it's going to be difficult to explain the
>> > > difference between the two formats in documentation, as the
>> > > implementation of the formats is a bit "into the weeds". The libvirt API
>> > > also specifies each format separately (kdump-zlib, kdump-lzo,
>> > > kdump-snappy) and so adding several new options there would be
>> > > unfortunate for end-users as well.
>> > >
>> > > At the end of the day, it's your judgment call, and I'll implement it
>> > > how you prefer.
>> >
>> > I just wanted to check back on this to clarify the next step. Are you
>> > satisfied with this and waiting to apply it until the right time? Or
>> > would you prefer me to send a new version making this opt-in?
>> >
>>
>> Nobody seems to raise concerns. If it would be just me, I would change
>> it. But we should rather be safe, so let's make it this opt-in please.
>>
>>
>
> Alex, Daniel, Thomas .. Do you have an opinion on changing the dump format?
>
> Stephen, do you have a new version of the patches to make it opt-in?

Thanks for the reminder, I did have a start on the patches, but they're
not quite ready to share just yet. I'm learning about the QMP command
JSON schemas, which I'll need to update. I ended up receiving a new work
laptop which disrupted my work. I'll try to get a new patch series out
during my Wednesday (US Pacific time) workday.

Thanks,
Stephen