现在我试图用Valgrind来解决这个问题.作为valgrind的第一个开始,我测试了一个perl hello world程序:
#! /usr/bin/perl use strict; use warnings; print "Hello world!\n";
这是运行valgrind时的valgrind输出–trace-children = yes perl ./hello_world.pl:
==12823== HEAP SUMMARY: ==12823== in use at exit: 290,774 bytes in 2,372 blocks ==12823== total heap usage: 5,159 allocs,2,787 frees,478,873 bytes allocated ==12823== ==12823== LEAK SUMMARY: ==12823== definitely lost: 13,981 bytes in 18 blocks ==12823== indirectly lost: 276,793 bytes in 2,354 blocks ==12823== possibly lost: 0 bytes in 0 blocks ==12823== still reachable: 0 bytes in 0 blocks ==12823== suppressed: 0 bytes in 0 blocks ==12823== Rerun with --leak-check=full to see details of leaked memory ==12823== ==12823== For counts of detected and suppressed errors,rerun with: -v ==12823== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 6 from 6)
从here开始,我的理解是,当alloc的数量不等于你有内存泄漏的自由数量时.
因为我正在做的就是打印你好世界,我不得不问这个问题,Perl解释器本身,这里是v5.10.1,至少有自己的内存泄漏,还是我解释的都是错的?
在我解决实际的perl脚本之前,我想了解这一点.
附录
我在Perl 5.12.0 delta看到以下内容:
A weak reference to a hash would leak. This was affecting DBI [RT #56908].
这可能最终适用于我的完整perl脚本,而不是这个hello world程序,但它让我觉得我应该经历安装最新版本的perl作为非root用户的痛苦.
ADDENDUM2
我安装了activestate perl 5.16.3,问题以及我实际脚本的问题仍然存在.
我怀疑在这个hello world程序的情况下,我必须使用/解释valgrind不正确,但我还不明白.
UPDATE1
达西姆的答案确实有所作为.当我在perl脚本中引入以下行时:
use Perl::Destruct::Level level => 1;
然后valgrind输出是:
==29719== HEAP SUMMARY: ==29719== in use at exit: 1,617 bytes in 6 blocks ==29719== total heap usage: 6,499 allocs,6,493 frees,585,389 bytes allocated ==29719== ==29719== LEAK SUMMARY: ==29719== definitely lost: 0 bytes in 0 blocks ==29719== indirectly lost: 0 bytes in 0 blocks ==29719== possibly lost: 0 bytes in 0 blocks ==29719== still reachable: 1,617 bytes in 6 blocks ==29719== suppressed: 0 bytes in 0 blocks ==29719== Rerun with --leak-check=full to see details of leaked memory ==29719== ==29719== For counts of detected and suppressed errors,rerun with: -v ==29719== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 6 from 6)
这是一个实质性的差异.我自己的内存泄漏问题仍然存在,但至少这个hello world程序现在对valgrind来说似乎是明智的.
这整个问题虽然引出了一个问题,但是如果在程序退出之前没有释放内存,那么使用Scalar :: Util停止硬循环引用有什么意义呢,禁止使用这个有点深奥的Perl :: Destruct :: Level模块???
解决方法
Allocated memory isn’t actually released unless 07001 is set because it’s faster to let the operating system handle this. PERL_DESTRUCT_LEVEL is only available for debugging builds or by using 07002 from perl.