Valgrind 摘要是什么意思？

Question

我运行我使用 Valgrind 的 Fortran 代码，这是摘要：

==7966== HEAP SUMMARY:
==7966==     in use at exit: 13,254 bytes in 19 blocks
==7966==   total heap usage: 340 allocs, 321 frees, 75,007 bytes allocated
==7966== 
==7966== LEAK SUMMARY:
==7966==    definitely lost: 0 bytes in 0 blocks
==7966==    indirectly lost: 0 bytes in 0 blocks
==7966==      possibly lost: 0 bytes in 0 blocks
==7966==    still reachable: 13,254 bytes in 19 blocks
==7966==         suppressed: 0 bytes in 0 blocks
==7966== Reachable blocks (those to which a pointer was found) are not shown.
==7966== To see them, rerun with: --leak-check=full --show-leak-kinds=all
==7966== 
==7966== For counts of detected and suppressed errors, rerun with: -v
==7966== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

1。一切都好吗？

==7966== total heap usage: 340 allocs, 321 frees, 75,007 bytes allocated

这意味着有些内存没有释放？我所有的变量都是静态的。

我的串行代码运行良好，但是当我使其与 OpenMP 并行并且对于大数据时，会出现 segmentation fault。这些记忆可能会导致这个问题吗？

编辑：我运行代码

valgrind --leak-check=yes ./a.out

这是摘要：

==9825== Conditional jump or move depends on uninitialised value(s)
==9825==    at 0x41630D9: log (w_log.c:28)
==9825==    by 0x804D052: MAIN__ (main.f90:225)
==9825==    by 0x804D128: main (main.f90:231)
==9825== 
==9825== Conditional jump or move depends on uninitialised value(s)
==9825==    at 0x4158E88: __ieee754_log (e_log.S:16)
==9825==    by 0x41630EF: log (w_log.c:42)
==9825==    by 0x804D052: MAIN__ (main.f90:225)
==9825==    by 0x804D128: main (main.f90:231)
==9825== 
==9825== HEAP SUMMARY:
==9825==     in use at exit: 0 bytes in 0 blocks
==9825==   total heap usage: 12,023 allocs, 12,023 frees, 96,007,152 bytes allocated
==9825== 
==9825== All heap blocks were freed -- no leaks are possible
==9825== 
==9825== For counts of detected and suppressed errors, rerun with: -v
==9825== Use --track-origins=yes to see where uninitialised values come from
==9825== ERROR SUMMARY: 2 errors from 2 contexts (suppressed: 0 from 0)

我找不到问题，这是第225行

       free_energy(d) = -log(abs(correlation_fun(d)))

Answer 1

根据此行，您正在泄漏内存：==7966== 仍可访问：19 个块中的 13,254 字节
尝试按照建议使用 --leak-check=full --show-leak-kinds=all 重新运行，并使用编译标志进行编译以跟踪哪些变量正在泄漏。即使变量是静态的，如果它们是堆分配的，它们仍然会泄漏内存。
段错误最好用 gdb 调试，但内存泄漏可能会导致它。

Answer 2

问题是未初始化变量的用法。您必须找出它是哪一个并确保它具有有意义的值。 没有完整的代码就没什么好说的了。很可能 d 的值没有正确定义。

仍然可以访问的内存通常是可以的。那是不是泄漏。通常，这些是您没有解除分配的可分配变量。它们可能在模块或主程序中或在其他任何地方声明为 save。它们不会在程序结束时自动释放，这通常不是问题。

真正的内存泄漏会导致问题，当您丢失指向某些内存的指针时，您将无法释放它。如果你重复这样做，你可能会浪费很多内存。然而，这在 valgrind 中看起来不同。然后您会看到 definitely lost、indirectly lost 或 possibly lost.

Valgrind 摘要是什么意思？

what does Valgrind summary mean?

fortran

valgrind

openmp

segmentation-fault