-Xcheck:memory option
The -Xcheck:memory option can help you identify memory leaks inside the JVM. The -Xcheck:memory option traces the JVM calls to the operating system's malloc() and free() functions, and identifies any JVM mistakes in memory allocation.
The system property -Dcom.ibm.dbgmalloc=true provides memory
allocation information about class library native code. Use this system property with the
-Xcheck:memory:quick,noscan,callsite=1000 option to obtain detailed information
about class library callsites and their allocation sizes. Here is some sample output:
total alloc | total freed | delta alloc | delta freed | high water | largest
blocks| bytes | blocks| bytes | blocks| bytes | blocks| bytes | blocks| bytes | bytes | num | callsite
-------+-------+-------+-------+-------+-------+-------+-------+-------+-------+-------+-------+------------
125 16000 0 0 0 0 0 0 125 16000 128 1 dbgwrapper/dbgmalloc.c:434
1 3661 1 3661 0 0 0 0 1 3661 3661 1 java/TimeZone_md.c:294
4144 18121712 4144 18121712 420 1836660 420 1836660 2 8746 4373 1 java/UnixFileSystem_md.c:373
10 124 10 124 0 0 0 0 2 55 51 1 java/jni_util.c:874
2 80797 2 80797 0 0 0 0 1 64413 64413 2 java/io_util.c:102
1 52 1 52 0 0 0 0 1 52 52 1 jli/java.c:2472
2 1872 1 264 0 0 0 0 2 1872 1608 2 net/linux_close.c:135
9 288 9 288 0 0 0 0 2 64 32 1 net/Inet6AddressImpl.c:280
99524 3260992980 99524 3260992980 10514 344503782 10515 344536549 1 32767 32767 1 net/SocketInputStream.c:93
3 24 3 24 0 0 1 8 2 16 8 1 net/linux_close.c:276
201 4824 0 0 0 0 0 0 201 4824 24 1 net/linux_close.c:149
311 1003152 261 496080 0 0 68 142128 119 651040 261360 45 zip/zip_util.c:655
311 31100 261 26100 0 0 68 6800 119 11900 100 1 zip/zip_util.c:230
243 15552 222 14208 0 0 85 5440 160 10240 64 1 zip/Inflater.c:61
1 64 1 64 0 0 0 0 1 64 64 1 zip/Deflater.c:76
146 7592 123 6396 3 156 74 3848 97 5044 52 1 zip/zip_util_md.c:75
3242 1443289 3241 1439991 25 4000 92 252856 71 262264 8192 679 zip/zip_util.c:917
311 125140 261 61724 0 0 68 17856 119 81500 32668 45 zip/zip_util.c:657
146 37376 123 31488 3 768 74 18944 97 24832 256 1 zip/zip_util_md.c:132For more information about the -Xcheck:memory option, see -Xcheck:memory in the OpenJ9 user documentation.