touch-packages team mailing list archive

[Michi Henning <michi.henning@xxxxxxxxxxxxx>]

I just downloaded the PPA from silo 4 and tried it on Mako.

I'm still seeing lots of requests with invalid size (-1, -1).

To reproduce, take a few photos and videos, run "thumbnailer-admin
clear", and start the gallery-app.

Looking at ~/.cache/upstart/application-click-
com.ubuntu.gallery_gallery_2.9.1.1209.log, I see a whole bunch of
requests with invalid size when I start the app.

Also, there appears to be another problem. (I'm watching
~/.cache/upstart/dbus.log for this.)

After I have my thumbnails on the events page, I can scroll all they way
to the right by swiping left. With the list positioned at the far right,
I briefly swipe left again. When I do that, I see that the app fires
around twenty requests within about 400 ms, all for the same single
image, all at size 256. I don't see why this should be necessary, seeing
that the thumbnails being asked for are sitting there on the screen
already.

Something similar happens when swipe right to to move the list back to
the beginning, and swipe right again. However, there, I see only two
requests, for two different thumbnails every time I swipe right. But,
again, why are these requests happening, when the widget is already
populated with thumbnails?

-- 
You received this bug notification because you are a member of Ubuntu
Touch seeded packages, which is subscribed to gallery-app in Ubuntu.
https://bugs.launchpad.net/bugs/1467743

Title:
  Lots of thumbnail requests with invalid size

Status in Canonical System Image:
  In Progress
Status in gallery-app package in Ubuntu:
  In Progress
Status in thumbnailer package in Ubuntu:
  New

Bug description:
  When using the ballery app, the thumbnailer gets loads of requests
  with QSize(-1,-1), for example, when opening the gallery app.

  The problem with this is that the thumbnailer interprets this to mean
  "give me the largest size you can (limited to a 1920x1920 bounding
  box). That's very expensive, especially in terms of disk space,
  because that 1920 "thumbnail" ends up going into the cache, needlessly
  hogging space.

  We are about to add a qWarning message to the QML side that reports
  invalid QSize requests. For now, we are going to retain the old
  behavior, but this will turn into an error soon.

  The most effective way to use the thumbnailer is to simply ask for an
  image in the desired size, with neither width nor height of -1. The
  thumbnailer will efficiently produce a thumbnail for that. (We do lots
  of internal caching to avoid extracting or downloading a thumbnail
  unnecessarily.)

  The thumbnailer may deliver a thumbnail that is smaller than what was
  asked for (because it never up-scales) so, if asked for a thumbnail of
  size 256, it's guaranteed not to be larger, but might be smaller (if
  the original image is smaller than what was asked for).

  Could you please adjust the gallery app behavior to ask for specific,
  valid sizes only?

  Running a tail -f on ~/.cache/upstart/dbus.log allows you to see the
  requests as they are made. Each request shows the size that was asked
  for.

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