Cachegrind interpretation

Question

Hi

I am using valgrind-cachegrind for my L2 cache bottlenecks and below is a single line output of the command

valgrind --tools=cachegrind EXECUTABLE

Output:

==3420== Cachegrind, an I1/D1/L2 cache profiler.
==3420== I   refs:      104,260,064,149
==3420== I1  misses:          1,678,402
==3420== L2i misses:            227,620
==3420== I1  miss rate:            0.00%
==3420== L2i miss rate:            0.00%

events: Ir I1mr I2mr Dr D1mr D2mr Dw D1mw D2mw
fl=???
fn=???
0 344827123 99754 17614 126416496 10253102 4816676 61417698 14508368 4860336
fn=A_FinalCommon
0 126 12 5 38 0 0 49 1 0
fn=A_Init
.........
........

I am baffled as to how Ir (Instruction cache read) shows up as 0. It shows 0 for all the functions in the cachegrind output.

Any pointers? Thanks. Bi