I am investigating a slow memory leak in a windows application using windbg
!heap -s gives the following output
Heap Flags Reserv Commit Virt Free List UCR Virt Lock Fast
(k) (k) (k) (k) length blocks cont. heap
-------------------------------------------------------------------------------------
00000023d62c0000 08000002 1182680 1169996 1181900 15759 2769 78 3 2b63 LFH
00000023d4830000 08008000 64 4 64 2 1 1 0 0
00000023d6290000 08001002 1860 404 1080 43 7 2 0 0 LFH
00000023d6dd0000 08001002 32828 32768 32828 32765 33 1 0 0
External fragmentation 99 % (33 free blocks)
00000023d8fb0000 08001000 16384 2420 16384 2412 5 5 0 3355
External fragmentation 99 % (5 free blocks)
00000023da780000 08001002 60 8 60 5 2 1 0 0
-------------------------------------------------------------------------------------
This shows that the heap with address 00000023d62c0000 has over a gigabyte of reserved memory.
Next I ran the command !heap -stat -h 00000023d62c0000
heap @ 00000023d62c0000
group-by: TOTSIZE max-display: 20
size #blocks total ( %) (percent of total busy bytes)
30 19b1 - 4d130 (13.81)
20 1d72 - 3ae40 (10.55)
ccf 40 - 333c0 (9.18)
478 8c - 271a0 (7.01)
27158 1 - 27158 (7.00)
40 80f - 203c0 (5.78)
410 79 - 1eb90 (5.50)
68 43a - 1b790 (4.92)
16000 1 - 16000 (3.94)
50 39e - 12160 (3.24)
11000 1 - 11000 (3.05)
308 54 - fea0 (2.85)
60 28e - f540 (2.75)
8018 1 - 8018 (1.43)
80 f2 - 7900 (1.36)
1000 5 - 5000 (0.90)
70 ac - 4b40 (0.84)
4048 1 - 4048 (0.72)
100 3e - 3e00 (0.69)
48 c9 - 3888 (0.63)
If I add up the total size of the heap blocks from the above command (4d130 + 3ae40 + ...) I get a few megabytes of allocated memory.
Am I missing something here? How can I find which blocks are consuming the gigabyte of allocated heap memory?
