Re: [PATCH 2/2] console/serial: bump buffer from 16K to 32K

[Roger Pau Monné <roger.pau@xxxxxxxxxx>]

On Thu, Jun 23, 2022 at 03:32:30PM +0200, Jan Beulich wrote:
> On 23.06.2022 11:08, Roger Pau Monne wrote:
> > Testing on a Kaby Lake box with 8 CPUs leads to the serial buffer
> > being filled halfway during dom0 boot, and thus a non-trivial chunk of
> > Linux boot messages are dropped.
> > 
> > Increasing the buffer to 32K does fix the issue and Linux boot
> > messages are no longer dropped.  There's no justification either on
> > why 16K was chosen, and hence bumping to 32K in order to cope with
> > current systems generating output faster does seem appropriate to have
> > a better user experience with the provided defaults.
> 
> Just to record what was part of an earlier discussion: I'm not going
> to nak such a change, but I think the justification is insufficient:
> On this same basis someone else could come a few days later and bump
> to 64k, then 128k, etc.

Indeed, and that would be fine IMO.  We should aim to provide defaults
that work fine for most situations, and here I don't see what drawback
it has to increase the default buffer size from 16kiB to 32kiB, and
I would be fine with increasing to 128kiB if that's required for some
use case, albeit I have a hard time seeing how we could fill that
buffer.

If I can ask, what kind of justification you would see fit for
granting an increase to the default buffer size?

Thanks, Roger.