[Aptitude-devel] Bug#438495: Cannot interrupt changelog download

[Manuel A. Fernandez Montecelo]

2015-09-21 21:25 GMT+01:00  <josh at freedesktop.org>:
> On Mon, Sep 21, 2015 at 08:33:57PM +0100, Manuel A. Fernandez Montecelo wrote:
>>
>> I am on a very slooooow connection, but even then the (and when
>> changelog is not on disk already) package changelog downloads so fast
>> that I cannot press 'q' before it downloads, except in a couple of
>> occasions.  Even with old packages (== assuming big changelog files) it
>> takes fractions of a second.
>
> Usually it's more of a connectivity issue; it doesn't take long to
> download once it starts, but occasionally I've had it take a long time
> to *start* getting data over the connection.  Latency, perhaps.

I tried to disconnect, but in that case the name resolution fails
right away.  I guess that the worst case is if DNS is slow or the
connection is slow to start, as you say.


>> Sometimes when pressing 'q', it seems to want to quit aptitude rather
>> than cancel the changelog (but there is the confirmation dialog).
>> However, assuming that in your case it's just very slow downloading the
>> changelog, I think that one can press F6 and cycle to another view and
>> continuing working there for a few seconds, as a workaround.
>>
>> To be honest, I am not sure if it's even a good idea to implement this
>> request, since I think the download happens in a background thread and
>> only creates the view (the one reacting to 'q') once the changelog is
>> ready.  So it's not a matter of simply connecting the 'q' event with
>> cancelling the download; perhaps it needs shuffling some code around and
>> creating new menus or keystrokes, that then need new messages and
>> translations and documentation, and I am not sure if the problem is so
>> inconvenient as to be worthwile?
>>
>> But maybe I am missing your use-case and why it's so annoying, please
>> explain.
>
> What made it annoying is that while the changelog downloads, aptitude
> blocks many other operations, just as it blocked operations while
> downloading packages ("You may not modify the state of any package while
> a download is underway.")

The message for downloads is still there, but one can stop the downloads.


> However, I can't seem to reproduce *that* part of the problem anymore.
> Has aptitude changed to allow background downloads of changelogs without
> blocking package state changes?  If so, then I think that brings this
> bug back to wishlist at most.

The relevant changes in this area are:

[2009-11-18]
Version 0.6.1                               "Instant toll logging."
  + [all] aptitude now has a generic global download queue.  This is
          actually implemented with the apt download queue object, but
          it runs all downloads in the background, integrates with
          aptitude's download cache, and provides support for getting
          status information on individual downloads and canceling
          them.

[2010-01-17]
Version 0.6.1.4                             "You can't take the sky from me."
  + [all] Download changelogs using the new internal download queue,
          not the download_manager system.  Fixes random crashes at
          shutdown.


Cheers.
-- 
Manuel A. Fernandez Montecelo <manuel.montezelo at gmail.com>