Intel 64 and IA-32 Architectures Software Developers Manual Volume 3B, System Programming Guide Part 2

Table Of Contents
A-188 Vol. 3
PERFORMANCE-MONITORING EVENTS
48H DCU_MISS_
OUTSTANDING
00H Weighted number of
cycles while a DCU miss is
outstanding, incremented
by the number of
outstanding cache
misses at any particular
time.
Cacheable read requests
only are considered.
Uncacheable requests
are excluded.
Read-for-ownerships are
counted, as well as line
fills, invalidates, and
stores.
An access that also
misses the L2 is
short-changed by 2
cycles (i.e., if counts
N cycles, should be
N+2 cycles).
Subsequent loads
to the same cache
line will not result in
any additional
counts.
Count value not
precise, but still
useful.
Instruction
Fetch Unit
(IFU)
80H IFU_IFETCH 00H Number of instruction
fetches, both cacheable
and noncacheable,
including UC fetches
81H IFU_IFETCH_
MISS
00H Number of instruction
fetch misses
All instruction fetches
that do not hit the IFU
(i.e., that produce
memory requests). This
includes UC accesses.
85H ITLB_MISS 00H Number of ITLB misses.
86H IFU_MEM_STALL 00H Number of cycles
instruction fetch is
stalled, for any reason.
Includes IFU cache
misses, ITLB misses, ITLB
faults, and other minor
stalls.
87H ILD_STALL 00H Number of cycles that
the instruction length
decoder is stalled.
Table A-18. Events That Can Be Counted with the P6 Family Performance-
Monitoring Counters (Contd.)
Unit
Event
Num.
Mnemonic Event
Name
Unit
Mask Description Comments