Font-related X-server bloat with GTK2?

[Brett Granger <bdgranger alum mit edu>]

I'm trying to track down a weird X-server memory consumption issue with 
a GTK2 app that I am working on.

I have an app with an rc file that requests some non-standard fonts. 
When I export the display of my machine to a different X server, I 
notice that launching the font consumes a rather large amount of memory 
in the X server (about 10 MB).  It seems to be related to the fact that 
the destination server doesn't have the fonts installed.  While the rc 
file is being parsed, I get messages to the effect of "Font <font> not 
found, falling back to Sans..."

The first time the app is launched, these failure messages come fairly 
slowly, as if the app were attempting to determine which font is the 
best match for the non-existent one.  However, if I kill the app, I 
regain about 6MB of the X server memory, and then when I launch the app 
again, the font failures happen instantaneously and I don't see the 
memory bloat any more until I restart the X server.

I built an instrumented X server and have been able to determine that 
the first time the app is launched I get about 44 OpenFont/QueryFont X 
protocol request pairs while the rc file is being parsed.  On all 
subsequent launches, I only get 4 requests instead of 44 -- I assume the 
X server must have cached the information that the font requested is not 
available?

So, is this a problem in GTK2 font initialization and handling (probably 
in Pango) where it's doing a lot of XLoadFont and then forgetting to 
XFreeFont, or is this likely to be a problem with the X server itself? 
If it makes any difference, I'm using Tiny X built from the X 4.2.0 
source tarballs.

If I remove the rc file so that I am requesting no fonts other than what 
GTK2 does by default, the memory still goes up by about 3MB with all the 
default font requests.  Then when I kill the app I get 2MB of that back 
and subsequent launches don't affect the size of X at all.  Why this 
first time hit, and not subsequent times?

The app is supposed to run in a limited memory environment, so I really 
need to find a way to avoid that first time hit, if possible.

Any thoughts or help appreciated!
--Brett Granger