UNC_C_TOR_INSERTS:MISS_OPCODE:OPC

本文详细介绍了Intel Sandy Bridge平台C-Box (Coherency Engine) Uncore PMU的功能与使用方法。该PMU针对每个物理核心提供了一个实例，支持8个独立的计数器，并提供了多种过滤选项，如节点过滤、核心过滤和线程过滤等，适用于双插槽系统的性能监控。

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转自：http://manpages.ubuntu.com/manpages/trusty/man3/libpfm_intel_snbep_unc_cbo.3.html

trusty (3) libpfm_intel_snbep_unc_cbo.3.gz

Provided by: libpfm4-dev_4.4.0-2_i386

NAME

       libpfm_intel_snbep_unc_cbo  -  support  for Intel Sandy Bridge-EP C-Box
       uncore PMU

SYNOPSIS

       #include <perfmon/pfmlib.h>

       PMU name: snbep_unc_cbo[0-7]
       PMU desc: Intel Sandy Bridge-EP C-Box uncore PMU

DESCRIPTION

       The library supports the Intel Sandy Bridge  C-Box  (coherency  engine)
       uncore PMU.  This PMU model only exists on Sandy Bridge model 45. There
       is one C-box PMU per physical core. Therefore there are eight identical
       C-Box  PMU  instances numbered frmo 0 to 7. On dual-socket systems, the
       number refers to the C-Box PMU on the socket where  the  program  runs.
       For  instance, if running on CPU8, then snbep_unc_cbo0 refers to the C-
       Box for physical core 0 on socket 1. Conversely, if  running  on  CPU0,
       then  the  same  snbep_unc_cbo0 refers to the C-Box for physical core 0
       but on socket 0.

       Each C-Box PMU implements 4 generic counters and a filter register used
       only with certain events and umasks.

MODIFIERS

       The  following  modifiers  are  supported  on  Intel Sandy Bridge C-Box
       uncore PMU:

       i      Invert the meaning of the event. The counter will now  count  C-
              Box  cycles  in  which  the  event  is  not occurring. This is a
              boolean modifier

       e      Enable edge detection, i.e., count only when there  is  a  state
              transition  from  no  occurrence  of  the  event to at least one
              occurrence. This modifier must  be  combined  with  a  threshold
              modifier  (t)  with  a value greater or equal to one.  This is a
              boolean modifier.

       t      Set the threshold value. When  set  to  a  non-zero  value,  the
              counter counts the number of C-Box cycles in which the number of
              occurrences of the event is greater or equal to  the  threshold.
              This is an integer modifier with values in the range [0:255].

       nf     Node   filter.   Certain   events,   such  as  UNC_C_LLC_LOOKUP,
              UNC_C_LLC_VICTIMS, provide a NID umask.  Sometimes  the  NID  is
              combined  with  other  filtering  capabilities, such as opcodes.
              The node filter is an 8-bit max bitmask. A node corresponds to a
              processor  socket.  The  legal  values  therefore depdend on the
              underlying hardware configuration. For dual-socket systems,  the
              bitmask has two valid bits [0:1].

       cf     Core  Filter.  This  is  a  3-bit filter which is used to filter
              based on phyiscal core origin of  the  C-Box  request.  Possible
              values  are  0-7.  If  the  filter  is  not  specified,  then no
              filtering takes place.

       tf     Thread Filter. This is a 1-bit filter which is used to filter C-
              Box   requests   based   on   logical  processor  (hyper-thread)
              identification. Possibles values are 0-1. If the filter  is  not
              specified, then no filtering takes place.

Opcode filtering

       Certain  events,  such as UNC_C_TOR_INSERTS supports opcode matching on
       the C-BOX transaction type.  To  use  this  feature,  first  an  opcode
       matching umask must be selected, e.g., MISS_OPCODE.  Second, the opcode
       to match on must be selected via  a  second  umasks  amongs  the  OPC_*
       umasks.   For  instance,  UNC_C_TOR_INSERTS:OPCODE:OPC_RFO,  counts the
       number of TOR insertions for RFO transactions.

       Opcode matching may  be  combined  with  node  filtering  with  certain
       umasks.  In  general  the  filtering  support is encoded into the umask
       name, e.g., NID_OPCODE supports both node  and  opcode  filtering.  For
       instance, UNC_C_TOR_INSERTS:NID_OPCODE:OPC_RFO:nf=1.

AUTHORS

       Stephane Eranian <eranian@gmail.com>

                                 August, 2012                        LIBPFM(3)