Where is this code not freeing memory ?

[jithoosin]

Hi
Let me first of all tell that this problem is not specific to a
compiler like gcc. It even comes in windows. So dont regard the
question as off topic.

I am posting a code using stl. I viewed the memory for program
by giving top command
eg: top -d 0.2 -p 'pid'
The pid will be printed out by the program itself.

Now coming to the question. The code is supposed to take around (200000
* 100 * 4 bytes = 76MB) .The top command at halfway point (line 41)
showed around 80MB. Until now it is correct. But after this i start
deleting elements from vector one by one. Then the code is supposed to
take lesser memory. But the top command showed still 80MB. Why is this
?
I then googled and read in
http://www-1.ibm.com/support/docview.wss?rs=994&context=SSSHAD&dc=DB5...
that stl "caches" memory and they gave a work around for it. I tried in
the code. Even that is not working.

Let me tell that valgrind or purify is not showing any leak in the
code. I some how need to free
from stl the memory. Is there any way ? Could any one help me ? I need
a general solution which is applicable for all stl containers. I cannot
wait for the program to terminate as i need to make more allocations
later

Thanks in advance
Regards
Kiran Pradeep

 

[Kai-Uwe Bux]

Hi
Let me first of all tell that this problem is not specific to a
compiler like gcc. It even comes in windows. So dont regard the
question as off topic.

I am posting a code using stl. I viewed the memory for program
by giving top command
eg: top -d 0.2 -p 'pid'
The pid will be printed out by the program itself.

Now coming to the question. The code is supposed to take around (200000
* 100 * 4 bytes = 76MB) .The top command at halfway point (line 41)
showed around 80MB. Until now it is correct. But after this i start
deleting elements from vector one by one. Then the code is supposed to
take lesser memory. But the top command showed still 80MB. Why is this
?
I then googled and read in
http://www-1.ibm.com/support/docview.wss?rs=994&context=SSSHAD&dc=DB5...
that stl "caches" memory and they gave a work around for it. I tried in
the code. Even that is not working.

Let me tell that valgrind or purify is not showing any leak in the
code. I some how need to free
from stl the memory. Is there any way ? Could any one help me ? I need
a general solution which is applicable for all stl containers. I cannot
wait for the program to terminate as i need to make more allocations
later

Design your own, non-caching allocator and make the STL containers use it.
All STL containers provide a hook for that in the second or third template
parameter.


Best

Kai-Uwe Bux