The !uniqstack extension displays all of the stacks for all of the threads in the current process, excluding stacks that appear to have duplicates.

!uniqstack [ -b | -v | -p ] [ -n ]


Causes the display to include the first three parameters passed to each function.

Causes the display to include frame pointer omission (FPO) information. On x86-based processors, the calling convention information is also displayed.

Causes the display to include the full parameters for each function that is called in the stack trace. This listing will include each parameter's data type, name, and value. This requires full symbol information.

Causes frame numbers to be displayed.


Windows 2000


Windows XP and later



This extension is similar to the k, kb, kc, kd, kp, kP, kv (Display Stack Backtrace) command, except that it does not display duplicate stacks.

For example:

0:000> !uniqstack
Processing 14 threads, please wait

.  0  Id: f0f0f0f0.15c Suspend: 1 Teb: 00000000`7fff8000 Unfrozen
      Priority: 0
Child-SP          Child-BSP         RetAddr
00000000`0006e5e0 00000000`00070420 00000000`6b009840
00000000`0006e600 00000000`000703d0 00000000`6b03db00
00000000`0006e950 00000000`000703b0 00000000`6b008520
00000000`0006e950 00000000`00070368 00000000`6b1845e0
00000000`0006e9b0 00000000`00070310 00000000`6b009980
00000000`0006e9d0 00000000`000702d0 00000000`6b009ff0
00000000`0006e9e0 00000000`00070248 00000000`77ea4a10
00000000`0006f290 00000000`000700e0 00000000`77ea5d60
00000000`0006f4c0 00000000`00070028 00000000`77ed6000
00000000`0006f550 00000000`00070000 00000000`77ed9000
00000000`0006f550 00000000`00070000 00000000`77ca78a0
00000000`0006fff0 00000000`00070000 00000000`00000000

.  1  Id: f0f0f0f0.718 Suspend: 1 Teb: 00000000`7fff4000 Unfrozen
      Priority: 0
Child-SP          Child-BSP         RetAddr
00000000`0043eb50 00000000`00440250 00000000`6b008520
00000000`0043eb80 00000000`00440208 00000000`6b1845e0
00000000`0043ebe0 00000000`004401a8 00000000`6b009980
00000000`0043ec00 00000000`00440168 00000000`6b009ff0
00000000`0043ec10 00000000`004400e0 00000000`77ea5f50
00000000`0043f4c0 00000000`00440028 00000000`77ed6000
00000000`0043f550 00000000`00440000 00000000`77ed9000
00000000`0043f550 00000000`00440000 00000000`7de05690
00000000`0043fff0 00000000`00440000 00000000`00000000

. 13  Id: f0f0f0f0.494 Suspend: 1 Teb: 00000000`7ef98000 Unfrozen
      Priority: 0
Child-SP          Child-BSP         RetAddr
00000000`00feffe0 00000000`00ff0040 00000000`77e94f30
00000000`00feffe0 00000000`00ff0040 00000000`00000000

Total threads: 14
Duplicate callstacks: 11 (windbg thread #s follow):
2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12