[XeTeX] xetex memory usage

[basketboy at bk.ru]

Hello,

I'm using MiKTeX 2.7 and xetex(xelatex) integrated in it. OS: Windows XP 
SP3.

My question is about memory usage of xetex. I've noticed that when I 
compile tex document, though this:

\documentclass{article}
\usepackage{fontspec}
\setmainfont{Arial}
\begin{document}
The quick brown fox jumps over the lazy dog.
\textbf{The quick brown fox jumps over the lazy dog.}
\emph{The quick brown fox jumps over the lazy dog.}
\end{document}


I see that it uses at least 130MB of RAM to generate pdf. So if for 
example I'm going to use xetex to generate pdf reports via webpage it 
can cause memory overusage. For example if 10 people start to generate 
pdfs simultaneously then 1300Mb of RAM will be used and it can cause the 
problems. We run into this problem already (with much more complex tex 
documents) and server with 512 MB of RAM and it was overloaded.

So my questions are the following:

1. Is this problem related with xetex or maybe fonts loading into 
memory? If it is not related to xetex then sorry, I'll try to find 
answer from MiKTeX users.

2. Is it possilbe to reduce RAM consumption in this case?

With regards, Andrey