Question

我在Ubuntu 12.04（精确）64位上使用R 2.15.3。如果我在valgrind中运行R：

R -d＆＃34; valgrind＆＃34; --vanilla

然后我使用q（）退出程序，我得到以下报告：

==7167== HEAP SUMMARY:
==7167==     in use at exit: 28,239,464 bytes in 12,512 blocks
==7167==   total heap usage: 28,780 allocs, 16,268 frees, 46,316,337 bytes allocated
==7167== 
==7167== LEAK SUMMARY:
==7167==    definitely lost: 120 bytes in 2 blocks
==7167==    indirectly lost: 480 bytes in 20 blocks
==7167==      possibly lost: 0 bytes in 0 blocks
==7167==    still reachable: 28,238,864 bytes in 12,490 blocks
==7167==         suppressed: 0 bytes in 0 blocks
==7167== Rerun with --leak-check=full to see details of leaked memory
==7167== 
==7167== For counts of detected and suppressed errors, rerun with: -v
==7167== Use --track-origins=yes to see where uninitialised values come from
==7167== ERROR SUMMARY: 385 errors from 5 contexts (suppressed: 2 from 2)

最近R经常崩溃，特别是当我通过Rcpp调用C ++函数时，这可能是原因吗？谢谢！

Answer 1

您可能误读了valgrind输出。最有可能的是，由于R作为一个系统被很好地研究，因此没有（明显的）泄漏。然而，R是一种动态类型语言，当然还有分配。 “绝对丢失：120字节”本质上是测量错误 - 请参阅valgrind文档。

如果您想查看泄漏，请创建一个，例如，使用如下文件：

library(Rcpp)
cppFunction('int leak(int N) {double *ptr = (double*) malloc(N*sizeof(double)); \
             return 0;}')
leak(10000)

保留记忆，即使是明确地超出R的范围，然后退出。我们得到：

$ R -d "valgrind" -f /tmp/leak.R
[...]
R> leak(10000)
[1] 0
R> 
==4479== 
==4479== HEAP SUMMARY:
==4479==     in use at exit: 35,612,126 bytes in 15,998 blocks
==4479==   total heap usage: 47,607 allocs, 31,609 frees, 176,941,927 bytes allocated
==4479== 
==4479== LEAK SUMMARY:
==4479==    definitely lost: 120 bytes in 2 blocks
==4479==    indirectly lost: 480 bytes in 20 blocks
==4479==      possibly lost: 0 bytes in 0 blocks
==4479==    still reachable: 35,611,526 bytes in 15,976 blocks
==4479==         suppressed: 0 bytes in 0 blocks
==4479== Rerun with --leak-check=full to see details of leaked memory
==4479== 
==4479== For counts of detected and suppressed errors, rerun with: -v
==4479== Use --track-origins=yes to see where uninitialised values come from
==4479== ERROR SUMMARY: 31 errors from 10 contexts (suppressed: 2 from 2)
$

现在有更多的泄漏（虽然它仍然没有人们希望的那么容易阅读）。如果您添加建议的标记，它最终将指向我们进行的malloc()调用。

另外，我在我的一个“带有R的HPC简介”幻灯片中的早期版本的CRAN包中有一个实际泄漏的实例。如果有泄漏，这会有所帮助。如果没有，就很难看透噪音。

简而言之，如果您编写崩溃代码，则可能是您的代码错误。尝试一个最小的可重复的例子是（好的）标准建议。

我的R有内存泄漏？

1 个答案: