我试图找出为什么free(3)不会将内存返回给系统。
我正在分配~11GB，呼叫malloc_info，释放，再次呼叫malloc_info。
但是我不理解malloc_info输出，特别是保留内存和当前使用的内存之间的区别。
$ uname -a
Linux gunda3 2.6.32-358.18.1.el6.x86_64 #1 SMP Wed Aug 28 17:19:38 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
/lib/libc.so.6
GNU C Library stable release version 2.12, by Roland McGrath et al.
Copyright (C) 2010 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.
Compiled by GNU CC version 4.4.7 20120313 (Red Hat 4.4.7-3).
Compiled on a Linux 2.6.32 system on 2013-08-27.
Available extensions:
The C stubs add-on version 2.1.2.
crypt add-on version 2.1 by Michael Glad and others
GNU Libidn by Simon Josefsson
Native POSIX Threads Library by Ulrich Drepper et al
BIND-8.2.3-T5B
RT using linux kernel aio
libc ABIs: UNIQUE IFUNC
For bug reporting instructions, please see:
<http://www.gnu.org/software/libc/bugs.html>.
-------------------- mallinfo.1分配11GB后-------------------
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--------------------------------- mallinfo.2 - 释放内存------- --------
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