memory check of /snes/example/tutorials/ex29.c

[(Rebecca) Xuefei YUAN]

Hi,

My own code has some left bytes still reachable according to valgrind,  
then I use two different version petsc (2.3.3-p15 and 3.0.0-p1) to  
compile and make the files, it gives me different number of bytes left  
still reachable. Moreover, I picked up the  
/snes/example/tutorials/ex29.c as another example, and found that some  
bytes are still reachable, what is the cause of it? It shows that it  
is from DACreate2D() and the I use -malloc_dump to get those unfreed  
informations.

I understand that for those 5 loss record, the 2nd, 3rd and 4th are  
true for all examples, but where do 1st and 5th ones come from? Also,  
the -malloc_dump information shows that there are
"[0]Total space allocated 37780 bytes",
but valgrind gives the information as
"==26628==    still reachable: 132,828 bytes in 323 blocks"

Why there is a big difference?

Thanks very much!

Rebecca

Here is the message from valgrind of running ex29:
==26628== 32 bytes in 2 blocks are still reachable in loss record 1 of 5
==26628==    at 0x4022AB8: malloc (vg_replace_malloc.c:207)
==26628==    by 0x86F9A78: MPID_VCRT_Create (mpid_vc.c:62)
==26628==    by 0x86F743A: MPID_Init (mpid_init.c:116)
==26628==    by 0x86D040B: MPIR_Init_thread (initthread.c:288)
==26628==    by 0x86CFF2D: PMPI_Init (init.c:106)
==26628==    by 0x8613D69: PetscInitialize (pinit.c:503)
==26628==    by 0x804B796: main (ex29.c:139)
==26628==
==26628==
==26628== 156 (36 direct, 120 indirect) bytes in 1 blocks are  
definitely lost in loss record 2 of 5
==26628==    at 0x4022AB8: malloc (vg_replace_malloc.c:207)
==26628==    by 0x429B3E2: (within /lib/tls/i686/cmov/libc-2.7.so)
==26628==    by 0x429BC2D: __nss_database_lookup (in  
/lib/tls/i686/cmov/libc-2.7.so)
==26628==    by 0x4732FDB: ???
==26628==    by 0x473413C: ???
==26628==    by 0x4247D15: getpwuid_r (in /lib/tls/i686/cmov/libc-2.7.so)
==26628==    by 0x424765D: getpwuid (in /lib/tls/i686/cmov/libc-2.7.so)
==26628==    by 0x8623509: PetscGetUserName (fuser.c:68)
==26628==    by 0x85E0CF0: PetscErrorPrintfInitialize (errtrace.c:68)
==26628==    by 0x8613E23: PetscInitialize (pinit.c:518)
==26628==    by 0x804B796: main (ex29.c:139)
==26628==
==26628==
==26628== 40 bytes in 5 blocks are indirectly lost in loss record 3 of 5
==26628==    at 0x4022AB8: malloc (vg_replace_malloc.c:207)
==26628==    by 0x429AFBB: __nss_lookup_function (in  
/lib/tls/i686/cmov/libc-2.7.so)
==26628==    by 0x4732FFB: ???
==26628==    by 0x473413C: ???
==26628==    by 0x4247D15: getpwuid_r (in /lib/tls/i686/cmov/libc-2.7.so)
==26628==    by 0x424765D: getpwuid (in /lib/tls/i686/cmov/libc-2.7.so)
==26628==    by 0x8623509: PetscGetUserName (fuser.c:68)
==26628==    by 0x85E0CF0: PetscErrorPrintfInitialize (errtrace.c:68)
==26628==    by 0x8613E23: PetscInitialize (pinit.c:518)
==26628==    by 0x804B796: main (ex29.c:139)
==26628==
==26628==
==26628== 80 bytes in 5 blocks are indirectly lost in loss record 4 of 5
==26628==    at 0x4022AB8: malloc (vg_replace_malloc.c:207)
==26628==    by 0x428839B: tsearch (in /lib/tls/i686/cmov/libc-2.7.so)
==26628==    by 0x429AF7D: __nss_lookup_function (in  
/lib/tls/i686/cmov/libc-2.7.so)
==26628==    by 0x4732FFB: ???
==26628==    by 0x473413C: ???
==26628==    by 0x4247D15: getpwuid_r (in /lib/tls/i686/cmov/libc-2.7.so)
==26628==    by 0x424765D: getpwuid (in /lib/tls/i686/cmov/libc-2.7.so)
==26628==    by 0x8623509: PetscGetUserName (fuser.c:68)
==26628==    by 0x85E0CF0: PetscErrorPrintfInitialize (errtrace.c:68)
==26628==    by 0x8613E23: PetscInitialize (pinit.c:518)
==26628==    by 0x804B796: main (ex29.c:139)
==26628==
==26628==
==26628== 132,796 bytes in 321 blocks are still reachable in loss  
record 5 of 5
==26628==    at 0x4022AB8: malloc (vg_replace_malloc.c:207)
==26628==    by 0x85EF3AC: PetscMallocAlign (mal.c:40)
==26628==    by 0x85F049B: PetscTrMallocDefault (mtr.c:194)
==26628==    by 0x81BCD3F: DACreate2d (da2.c:364)
==26628==    by 0x804BAFB: main (ex29.c:153)
==26628==
==26628== LEAK SUMMARY:
==26628==    definitely lost: 36 bytes in 1 blocks.
==26628==    indirectly lost: 120 bytes in 10 blocks.
==26628==      possibly lost: 0 bytes in 0 blocks.
==26628==    still reachable: 132,828 bytes in 323 blocks.
==26628==         suppressed: 0 bytes in 0 blocks.


-- 
(Rebecca) Xuefei YUAN
Department of Applied Physics and Applied Mathematics
Columbia University
Tel:917-399-8032
www.columbia.edu/~xy2102