Language packs and desktop entries

[Alexander Larsson]

On Wed, 2005-06-08 at 15:33 +0900, Takao Fujiwara - Tokyo S/W Center
wrote:
> Excellent summary. Thanks for the valuable discussions.
> 
> Mark McLoughlin wrote:
> > Hey,
> > 	To summarise the discussion we had at GUADEC around this issue, we
> > talked about two solutions.
> > 
> >   1) Put the translation domain for the app in the .desktop file and
> >      have .desktop file parsers pull the translations from the 
> >      approriate message catalog.
> > 
> >      This is nice from the point of view that it would solve the 
> >      language packs issue very cleanly and that (at least in GNOME) the 
> >      translations are already in the message catalog.
> > 
> >      First problem is the performace hit with having to read every app's
> >      message catalog. We're already seeing problems because of the 
> >      amount of disk seeking involved with loading every .desktop file. 
> >      Add message catalogs into the equation and you now have to locate 
> >      each message catalog (by stat()ing for each locale alias) and 
> >      load it.
> 
> Yes, this is right. But .mo is a binary and .destop is a text file. So for the milestone, If we change almost .desktop files to .mo files, I think the
> performance will be faster rather than the current implementations. One solution is to use one .mo file for the .desktop file.

I think you are misunderstanding what the performance problem is. The
problem is the need to open multiple files (both desktop and mo), and
for .mo file its even worse, as it requires multiple stats to locate the
right translation. Each stat of a file means a seek, and two seeks for
an open. Each seek is on average half a rotational delay on the HD,
which is a very long time in cpu clock cycles. Actually reading the file
once we've seeked to it is not a problem, relatively.

In fact, the stating and opening of many files in for instance the icon
theme spec has caused massive performance issues for implementations,
and we do *not* want that to happen again.

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 Alexander Larsson                                            Red Hat, Inc 
                   alexl at redhat.com    alla at lysator.liu.se 
He's a superhumanly strong Jewish dwarf with no name. She's a provocative 
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