mpi - 使用 valgrind 发现 mpi 代码中的错误

Question

我有一个完美的串行代码，但使用 mpirun -n 2 ./out它给出了以下错误:

./out': malloc(): smallbin double linked list corrupted: 0x00000000024aa090

我尝试使用 valgrind，例如:

valgrind --leak-check=yes mpirun -n 2 ./out

我得到以下输出:

==3494== Memcheck, a memory error detector
==3494== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==3494== Using Valgrind-3.11.0 and LibVEX; rerun with -h for copyright info
==3494== Command: mpirun -n 2 ./out
==3494== 
Grid_0/NACA0012.msh
Grid_0/NACA0012.msh
>>> Number of cells: 7734
>>> Number of cells: 7734
0.000000  0         1.470622e-02
*** Error in `./out': malloc(): smallbin double linked list corrupted: 0x00000000024aa090 ***

===================================================================================
=   BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES
=   PID 3497 RUNNING AT orhan
=   EXIT CODE: 134
=   CLEANING UP REMAINING PROCESSES
=   YOU CAN IGNORE THE BELOW CLEANUP MESSAGES
===================================================================================
YOUR APPLICATION TERMINATED WITH THE EXIT STRING: Aborted (signal 6)
This typically refers to a problem with your application.
Please see the FAQ page for debugging suggestions
==3494== 
==3494== HEAP SUMMARY:
==3494==     in use at exit: 131,120 bytes in 2 blocks
==3494==   total heap usage: 1,064 allocs, 1,062 frees, 231,859 bytes allocated
==3494== 
==3494== LEAK SUMMARY:
==3494==    definitely lost: 0 bytes in 0 blocks
==3494==    indirectly lost: 0 bytes in 0 blocks
==3494==      possibly lost: 0 bytes in 0 blocks
==3494==    still reachable: 131,120 bytes in 2 blocks
==3494==         suppressed: 0 bytes in 0 blocks
==3494== Reachable blocks (those to which a pointer was found) are not shown.
==3494== To see them, rerun with: --leak-check=full --show-leak-kinds=all
==3494== 
==3494== For counts of detected and suppressed errors, rerun with: -v
==3494== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

我不擅长 valgrind，但我理解的是 valgrind 认为没有问题。 valgrind 是否有更好的选择来发现提到的特定错误的来源？

Answer 1

请注意，通过上面的调用，

valgrind --leak-check=yes mpirun -n 2 ./out

您正在程序上运行 valgrind mpirun ，大概已经过广泛测试并且可以正常工作，而不是程序 ./out ，你知道这有问题。

要在您的测试程序上运行 valgrind，您需要执行以下操作:

mpirun -n 2 valgrind --leak-check=yes ./out

其中使用 mpirun 启动 2 个进程，每个进程运行 valgrind --leak-check=yes ./out .