[mythtv-users] Front end memory usage

[Robert Johnston]

On 30/10/05, Michael T. Dean <mtdean at thirdcontact.com> wrote:
> Alberto Alonso wrote:
>
> >I am finding more info on this. It seems to be mostly
> >related to theme and resolution. Going down to 640x480
> >I now get 57M of RES usage, which is a heck of a lot
> >better, but still rather large if you ask me.
> >
> >What theme and resolution are you using to the 17M
> >resident?
> >
> >Also, does anybody know of any setting to set things up
> >that maybe doesn't cache the whole theme stuff to memory?
> >It seems that reading from disk on a page change should be
> >fast enough.
> >
> >
> I'm using Minimalist-wide (which is appropriate for widescreen TV's).
>
> Another Myth box I maintain shows:
>
>   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
> 32076 root      15   0 69764  26m  18m S  6.3  5.3 752:49.75 mythfrontend
>
> And the guy who owns it uses visor--the theme with the clouds (a
> "complex" background image)--at 1024x768.
>
> I really don't think it's the theme's being cached that's causing the
> problem.  The default theme, as distributed (XML descriptions and
> "unscaled" images), is only 2736KB, Minimalist wide is 2900KB, and visor
> is 2828KB.  On disk, my themecache (the scaled
> images)--Minimalist-wide.1920.1080--is 7776KB, and visor.1024.768 is
> 5712KB.  Also, TTBOMK, Myth doesn't maintain the entire theme in
> memory.  Images are cached on disk as just described.  Also, since it
> notices changes to the XML theme files at runtime, it may not even keep
> the theme descriptions in memory (although I haven't looked at the
> source to verify this--it could also be checking modification times or
> something).
>
> Regardless, I can't see the theme causing it to take 50-100MB of RAM.
> Maybe for a program like Windows Media Player, but this is MythTV.  ;)

Remember that those theme images are stored (on disk) in a compressed
form. I believe a QImage is the raw bitmap, uncompressed, in memory.
So a 1024x768x32-bit image would be 3MiB (25165824 bits)
--
Robert "Anaerin" Johnston