Bug#1068890: diffoscope: --hard-timeout option

[Chris Lamb]

Vagrant Cascadian wrote:

> On 2024-04-16, Chris Lamb wrote:
>> However, I think this first iteration of --hard-timeout time has a few
>> things that would need ironing out first, and potentially make it not
>> worth implementing:
>>
>> (1) You suggest it should start again with "--max-container-depth 3",
>> but it would surely need some syntax (or another option?) to control
>> that "3" (but for the second time only).
>
> What about going the other direction ... starting with a very small
> value for max-container-depth, and incrementally increasing it,
> generating a report (or at least storing sufficient data to generate
> one) in between each increment, so you always get some information, but
> essentially incrementally increase the resolution?
>
> Or would that approach just be too inefficient?

This is probably a separate required best suited to another  issue  at
this point, but I do like the idea  of  being  able  to  incrementally
increase the resolution over time.  Depending  on  how  it  worked  in
practice, there should not be significant overhead  in  managing  this
if, say, the commands that could not be run "in time" would have token
placeholders internally that rendered to text  in  the  output  rather
than non-trivial/expensive binary diffs.

On the negative side though, I think this would still require a robust
way of killing long-running processes  as  outlined  previously.   But
moreover it would require a HUGE reworking of how  diffoscope  handles
containers and recurses into nested structures in its tree-like style.
Indeed, thinking about it, this change would pretty  much  be  exactly
the same work needed to make diffoscope  run  in  parallel  (!)  which
hopefully communicates both the scope of the  changes  that  would  be
needed to achieve this, and that making  diffoscope  run  in  parallel
also  has   other   benefits.    Anyway,   mini   brain   dump   over.


Regards,

-- 
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