Windows Task Manager Memory Usage Issue

[alex.j.k2]

Hello,


I am currently running a C++ program which is supposed to compute
something in about three
full (24 hours) days.

I am a little panicked about the feedback I get from the Windows
Task Manager about my program.

More specifically, after I minimize the console application that
is doing the computation, the Task Manager shows a very small (but
growing) amount of memory (7Mb or so) being used by my program, but I
know that my program, after some initializations, should use at least
300Mb (and maximum 500Mb, when the dynamically allocated memory is at
the maximum).

This makes me worry (hopefully irrationally) that Windows has done
something --deallocated? -- with part of the memory that my program
uses. A good sign is that the "commit charge" did not decrease, so I
still hope that I am just witnessing a weird way of showing memory
usage in the Task Manager and not anything more sinister.

Can anyone with knowledge of how the Task Manager shows memory
usage make me get rid of my fears?

Alex

P.S. I am using Windows XP. If other information about my system would
be needed, please let me know.

 

[HeyBub]

Hello,


I am currently running a C++ program which is supposed to compute
something in about three
full (24 hours) days.

I am a little panicked about the feedback I get from the Windows
Task Manager about my program.

More specifically, after I minimize the console application that
is doing the computation, the Task Manager shows a very small (but
growing) amount of memory (7Mb or so) being used by my program, but I
know that my program, after some initializations, should use at least
300Mb (and maximum 500Mb, when the dynamically allocated memory is at
the maximum).

This makes me worry (hopefully irrationally) that Windows has done
something --deallocated? -- with part of the memory that my program
uses. A good sign is that the "commit charge" did not decrease, so I
still hope that I am just witnessing a weird way of showing memory
usage in the Task Manager and not anything more sinister.

Can anyone with knowledge of how the Task Manager shows memory
usage make me get rid of my fears?

Alex

P.S. I am using Windows XP. If other information about my system would
be needed, please let me know.

Does your project, like all good projects should, give you any indication
that it is progressing to a satisfactory conclusion?

Or do you just have to wait three days to find out it wasn't really
pregnant?

 

[alex.j.k2]

Does your project, like all good projects should, give you any indication
that it is progressing to a satisfactory conclusion?

Or do you just have to wait three days to find out it wasn't really
pregnant?

It does, but I do not check every possible way in which the
computation might go wrong, as that would be too expensive. The issue
though, is the way Windows Task Manager displays memory usage, not
what my program displays.

I checked that the same memory usage display happens with most
other programs, so I am probably too paranoid about this, but better
safe than sorry.

It would still be nice to know exactly what the Task Manager
displays -- it seems weird to me that minimizing an application should
have that effect.

Alex

 

[John John (MVP)]

That is normal, when you minimize an application the Working set will or
may be aggressively trimmed, it isn't unusual to have a maximized
application that is using a couple hundred of MB of RAM have its Working
Set trimmed to 4 or 5 MB when it is minimized, how much RAM is available
may affect how aggressively the Working Set is trimmed. You should ask
your fellow programmers in a programing group how to have the
application keep or ask for more memory when it is minimized.

John

 

[alex.j.k2]

That is normal, when you minimize an application the Working set will or
may be aggressively trimmed, it isn't unusual to have a maximized
application that is using a couple hundred of MB of RAM have its Working
Set trimmed to 4 or 5 MB when it is minimized, how much RAM is available
may affect how aggressively the Working Set is trimmed. You should ask
your fellow programmers in a programing group how to have the
application keep or ask for more memory when it is minimized.

John

Thank you.

I also found out about the working set trimming here:

http://support.microsoft.com/default.aspx?scid=kb;en-us;293215

So this will negatively affect temporarily the performance of the
program,
but not its function.

Since I have full control of the machine, just abstaining from
minimizing
the application is the most convenient solution for now. But it's good
to
know about this issue.

Alex

 

[John John (MVP)]

Thank you.

I also found out about the working set trimming here:

http://support.microsoft.com/default.aspx?scid=kb;en-us;293215

So this will negatively affect temporarily the performance of the
program,
but not its function.

Since I have full control of the machine, just abstaining from
minimizing
the application is the most convenient solution for now. But it's good
to
know about this issue.

Thanks for the link.

John