內存分配錯誤的OpenCV cvReleaseMat

Question

CvMat* traindata=cvCreateMat(1000,36,CV_32FC1); 

當我嘗試着發佈使用cvReleaseMat(&trainData)

我發現在任務管理器的內存沒有減少這個矩陣...，而不是本次發佈命令沒有對這種記憶任何影響在任務管理器中應用。

我的疑問是...... cvReleaseMat是否釋放CPU中的內存？或者它是否僅僅使矩陣在未來不可見？

Answer 1

是的cvReleaseMat確實釋放了內存。任務管理器並不是真正的查看CvMat *分配內存的工具。雖然如果你想使矩陣大得多，你可能會注意到它。該矩陣佔用1000 * 36 * 4 = 144000字節。

你可以看到它回到下面的代碼由Valgrind的分析輸出：

CvMat* traindata = cvCreateMat(1000, 36, CV_32FC1); 
//cvReleaseMat(&traindata); 

相關Valgrind的輸出是：

==4967== HEAP SUMMARY: 
==4967==  in use at exit: 144,108 bytes in 2 blocks 
==4967== total heap usage: 10 allocs, 8 frees, 144,772 bytes allocated 
==4967== 
==4967== LEAK SUMMARY: 
==4967== definitely lost: 64 bytes in 1 blocks 
==4967== indirectly lost: 144,044 bytes in 1 blocks 
==4967==  possibly lost: 0 bytes in 0 blocks 
==4967== still reachable: 0 bytes in 0 blocks 
==4967==   suppressed: 0 bytes in 0 blocks 

但如果你真的放開CvMat

CvMat* traindata = cvCreateMat(1000, 36, CV_32FC1); 
cvReleaseMat(&traindata); 

你得到這個輸出結果現在注意到valgrind的輸出：

==4957== HEAP SUMMARY: 
==4957==  in use at exit: 0 bytes in 0 blocks 
==4957== total heap usage: 10 allocs, 10 frees, 144,772 bytes allocated 
==4957== 
==4957== All heap blocks were freed -- no leaks are possible