求助：glib 2.40.2 疑似内存泄漏问题

eglic_cu

初次使用Glib，代码基本写完之后，顺手测试下，发现
GHashTable内存泄漏问题，不知是否使用方式不对？
另：g_key_file_new .. g_key_file_load_from_file ... g_key_file_free 同样问题。。

精简后最小测试代码如下：

#include <glib.h>
int main(int argc,char **argv){
        printf("glib version = %d.%d.%d\n",glib_major_version,glib_minor_version,glib_micro_version);
        GHashTable *h = g_hash_table_new(NULL,NULL);
        g_hash_table_destroy(h);
}

编译后运行之
valgrind --db-attach=yes --tool=memcheck --leak-check=full --show-leak-kinds=all ./test.bin

glib version = 2.40.2
==27702== HEAP SUMMARY:
==27702==     in use at exit: 2,076 bytes in 3 blocks
==27702==   total heap usage: 6 allocs, 3 frees, 2,260 bytes allocated
==27702==
==27702== 4 bytes in 1 blocks are still reachable in loss record 1 of 3
==27702==    at 0x4C2AB80: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==27702==    by 0x56B08CD: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x56B0D28: g_private_get (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x568A20C: g_slice_alloc (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x565E17D: g_hash_table_new_full (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x4019E0: do_test_ini (test.c:122)
==27702==    by 0x40157A: main (test.c:24)
==27702==
==27702== 40 bytes in 1 blocks are still reachable in loss record 2 of 3
==27702==    at 0x4C2AB80: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==27702==    by 0x56B058F: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x56B0634: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x56B0978: g_mutex_lock (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x5640D71: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x568A374: g_slice_alloc (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x565E17D: g_hash_table_new_full (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x4019E0: do_test_ini (test.c:122)
==27702==    by 0x40157A: main (test.c:24)
==27702==
==27702== 2,032 bytes in 1 blocks are still reachable in loss record 3 of 3
==27702==    at 0x4C2CC70: calloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==27702==    by 0x5674668: g_malloc0 (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x5641015: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x568A374: g_slice_alloc (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x565E17D: g_hash_table_new_full (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4002.0)
==27702==    by 0x4019E0: do_test_ini (test.c:122)
==27702==    by 0x40157A: main (test.c:24)
==27702==
==27702== LEAK SUMMARY:
==27702==    definitely lost: 0 bytes in 0 blocks
==27702==    indirectly lost: 0 bytes in 0 blocks
==27702==      possibly lost: 0 bytes in 0 blocks
==27702==    still reachable: 2,076 bytes in 3 blocks
==27702==         suppressed: 0 bytes in 0 blocks
==27702==
==27702== For counts of detected and suppressed errors, rerun with: -v
==27702== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

zsszss0000

为啥提示找不到<glib.h>?

eglic_cu

zsszss0000 发表于 2014-12-19 08:47
为啥提示找不到?

直接 #include </usr/include/glib-2.0/glib.h>
或者 #include <glib-2.0/glib.h>

密林三木

glibc把malloc的内存不会归还给系统的，你可以直接malloc然后free同样会有这个问题。

myworkstation

回复 1# eglic_cu

试试这样运行：G_DEBUG=gc-friendly G_SLICE=always-malloc valgrind --db-attach=yes --tool=memcheck --leak-check=full --show-leak-kinds=all ./test.bin
因为glib有自己的内存管理策略，destory之类的函数并不表示把内存还给系统，也可以是还给glib的内存池，为了尽量消除glib自身内存策略的影响加上G_DEBUG=gc-friendly G_SLICE=always-malloc
   

eglic_cu

密林三木 发表于 2014-12-19 13:22
glibc把malloc的内存不会归还给系统的，你可以直接malloc然后free同样会有这个问题。

我用 g_malloc  和 g_free 没有问题的呀？

eglic_cu

myworkstation 发表于 2014-12-19 14:32
回复 1# eglic_cu

试试这样运行：G_DEBUG=gc-friendly G_SLICE=always-malloc valgrind --db-attach=ye ...

那这样的程序在服务器上长期用crond运行可靠吗（每小时运行一次）？
会不会导致服务器内存耗尽？
如果是的话，有没有什么办法可以不重启服务器来回收这些内存？

myworkstation

回复 7# eglic_cu


    进程退出时进程所占用的内存就被释放了，这是系统的行为。不用担心进程退出时有内存泄露。

eglic_cu

myworkstation 发表于 2014-12-20 10:27
回复 7# eglic_cu

好的，我在试试。

daxiguagg

hi.baidu.com/mcsekpfxhebikmq/item/b36fc5ee60ffcfd92a09a4bd
楼主可以看看这篇文章，手动试下就知道