New subject: Absolute limit to RAM used by Amelia for Windows?

26 May 2003

That makes sense, of course.  

But how much is too much?  I may have misunderstood the instructional 
comments in the configuration file.  But I take them to mean that one 
can avoid the disk swapping performance penalty by setting the 
max_workspace parameter to ((available physical memory)-2MB).  I have 
set the parameter to ((available physical memory)-(~200MB)).  Have I 
misinterpreted the instructions?

----- Original Message -----
From: Gary King &lt;king(a)harvard.edu&gt;
Date: Monday, May 26, 2003 5:00 pm
Subject: Re: [amelia] Absolute limit to RAM used by Amelia for Windows?

...

 If you ask for too much memory, then you will be requiring Gauss 
 to swap
 memory to disk.  So although I wish Gauss computed all this 
 automatically,it doesn't.  So you're in the position of having to 
 get it right.  Too
 little and it can bomb out, and too much and it will get slower.  
 (If a
 run works in a given amount of memory, then adding memory will not 
 usuallymake it faster.)
 Gary

 On Mon, 26 May 2003 joew(a)georgetown.edu wrote:

  It's possible that the Windows 2000 Task
Manager's "Processes"   window 
  does not report the memory that the Gauss
run-time module uses   as work 
  space.  Perhaps the window reports only the
memory allocated to   the 
  module's executing program code.

 Hence it may be useful to mention that increasing the work space 
 configuration values in the config file and, later, adding 512MB   of 
  physical RAM did not reduce the amount of time
required to   generate 
  a "50 draws" report during the
importance sampling stage.

 Also, I added a "workspace=250.0" line to the config file, in   addition

  to the "max_workspace=300.0"  The
amount of time to get 50 draws 
 actually _increased_ from ~32 minutes to ~39 minutes.  (Wonder   whether 
 > I hit some virtual memory-triggering wall?)
 > 
 > Thanks again in advance for any help with this.
 >  