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

Table Of Contents
Vol. 3 A-13
PERFORMANCE-MONITORING EVENTS
28H 02H L1D_WB_L2.S_STAT
E
Counts number of L1 writebacks to
the L2 where the cache line to be
written is in the S state.
28H 04H L1D_WB_L2.E_STAT
E
Counts number of L1 writebacks to
the L2 where the cache line to be
written is in the E (exclusive) state.
28H 08H L1D_WB_L2.M_STAT
E
Counts number of L1 writebacks to
the L2 where the cache line to be
written is in the M (modified) state.
28H 0FH L1D_WB_L2.MESI Counts all L1 writebacks to the L2 .
2EH 4FH LONGEST_LAT_CACH
E.REFERENCE
This event counts requests
originating from the core that
reference a cache line in the last
level cache. The event count
includes speculative traffic but
excludes cache line fills due to a L2
hardware-prefetch. Because cache
hierarchy, cache sizes and other
implementation-specific
characteristics; value comparison to
estimate performance differences
is not recommended.
see Table A-1
2EH 41H LONGEST_LAT_CACH
E.MISS
This event counts each cache miss
condition for references to the last
level cache. The event count may
include speculative traffic but
excludes cache line fills due to L2
hardware-prefetches. Because
cache hierarchy, cache sizes and
other implementation-specific
characteristics; value comparison to
estimate performance differences
is not recommended.
see Table A-1
3CH 00H CPU_CLK_UNHALTED
.THREAD_P
Counts the number of thread cycles
while the thread is not in a halt
state. The thread enters the halt
state when it is running the HLT
instruction. The core frequency
may change from time to time due
to power or thermal throttling.
see Table A-1
Table A-2. Non-Architectural Performance Events In the Processor Core for Intel Core
i7 Processors
Event
Num.
Umask
Value
Event Mask
Mnemonic Description Comment