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From: wojtek@power.com.pl (Wojtek Narczynski)
Newsgroups: comp.lang.ada
Subject: Re: Is the Ada run-time required to detect out-of-memory conditions?
Date: 21 May 2004 16:41:21 -0700
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Hello,

> Now, 2940 MiB / 192_650_250 iterations averages 16 bytes per
> allocation.  Each Integer is theoretically only 4 bytes.  So, while
> libgnat does indeed reuse previously allocated pages, there is a
> non-negligible overhead.  Part of this may be due to the necessary
> bookkeeping structures in the C library (malloc), but do you think
> this might explain such a huge (4x) overhead?

Here is a description of how it works:

http://gee.cs.oswego.edu/dl/html/malloc.html

Indeed 16 bytes are supposed to be allocated, according to this
document.


When I actually write the allocated space, i get "Killed" for almost
any size of chunk... And yes, I do have "May 22 01:17:00 slooby
kernel: VM: killing process memory_chunk" messages in my syslog...


I would be interested in finding out wether this is specific to Linux,
and how about kernel 2.6.


Regards,
Wojtek