need to limit or disable files being retained in memory or cache

From: Cyndee (anonymous_at_discussions.microsoft.com)
Date: 09/03/04 

Date: Fri, 3 Sep 2004 08:41:18 -0700

I have two laptops (Compaq presario 1500, Dell Inspiron
1100 - both Pentium 4, both 2 GHz +, both have 512 mb
memory) The purpose of these laptops is to use in a
medical neurosurgery clinic to view patient CT scans while
the patient is there (supplaments - negative type films)

The problem -
The CT scans come on a disk from another hospital. The
disk contains a viewing program (I do not want to mention
the name). The viewing program loads in a browser window
and gives the user an option to view images. At that
point, there are usually several directories. I have been
choosing the one with the most images (200 +) for my
testing. The images take a fairly long time to load 1 - 3
minutes. Understanding that the DVD/CD rom is the
bottleneck, through tweaking of the system - I have been
able to reduce the load of a 220 image file from 3 mins to
1min 15 secs (on both machines).

As each CD is loaded, the images are being retained and
not released. In my testing I noticed that if I load the
CD images, shut the program down but not the computer,
reinsert the CD, the images will load in about 2 secs or
less. That tells me that they are in memory somewhere.
(If I turn the computer all the way off, they have to
reload from scratch again). I called the viewer vendor
who told me that they purge their images when the program
is shut down. That may be but something is keeping them
either in memory or in cache. They said that Windows XP
was doing it. I don't know how to prove or disprove that
but it doesn't matter because my relationship with the
vendor is indirect and I really don't have the right to
make any kind of demand at all.

Here is what I would like to do if possible. When the CD
loads, I don't want the images to be cached at all. The
doctor is going to look at the scans only when the patient
is there and will not look at the same scans in that
clinic again.

What I have done in my previous tweaking was to disable
everything in the startup window and most everything in
the services window. I adjusted the performance for best
performance which eliminated all of the check boxes in
that window. The processor scheduling is for programs and
so is the memory useage. Those changes seemed to allow me
to reduce the load time. Now, I have changed the page
size from the recommended 766 mb to 2048 with a maximum of
4096 in hopes that it will buy enough space to let them
get through an entire clinic. I plan to buy more memory
to double the size but I really wanted to see if my new
changes would help

And of course, if I could prevent these images from being
cached in the first place, that would solve the problem
altogether - I think.

Any advice from anyone?

Relevant Pages

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  • Re: need to limit or disable files being retained in memory or cache
    ... The viewing program loads in a browser window ... > and gives the user an option to view images. ... In my testing I noticed that if I load the ... That tells me that they are in memory somewhere. ...
    (microsoft.public.windowsxp.perform_maintain)
  • creating garbage collectable objects (caching objects)
    ... I'm performing operations on multiple images and would like compromise ... The fast approach would load all images upfront and create then multiple ... that I do not have enough memory to load ...
    (comp.lang.python)
  • Re: need to limit or disable files being retained in memory or cache
    ... The viewing program loads in a browser window ... > and gives the user an option to view images. ... In my testing I noticed that if I load the ... That tells me that they are in memory somewhere. ...
    (microsoft.public.windowsxp.perform_maintain)