Intel PCM Column Names Decoder Ring

When Intel Performance Counter Monitor (Intel PCM) is generating csv files as output, short names are used as column headers. This helps to keep the table width at a manageable size if the data is loaded in a spreadsheet program. However, it makes it rather hard to guess what exactly is hiding behind these abbreviations. Since I'm getting a lot of questions on how to interpret these column names, I've put together a decoder ring:

Field Explanation Example
The following metrics are available on all levels:
Date Day-Month-Year 05-02-14
Time Time of day 13:38:04
EXEC Instructions per nominal CPU cycle, i.e. in respect to the CPU frequency ignoring turbo and power saving 0.182
IPC Instructions per cycle. This measures how effectively you are using the core. 0.159
FREQ Frequency relative to nominal CPU frequency (“clockticks”/”invariant timer ticks”) 1.143
AFREQ Frequency relative to nominal CPU frequency excluding the time when the CPU is sleeping 1.143
L3MISS L3 cache line misses in millions 182.879
L2MISS L2 cache line misses in millions 356.3
L3HIT L3 Cache hit ratio (hits/reference) 0.487
L2HIT L2 Cache hit ratio (hits/reference) 0.233
L3CLK Very rough estimate of cycles lost to L3 cache misses vs. clockticks 0.044
L2CLK Very rough estimate of cycles lost to L2 cache misses vs. clockticks 0.008
The following metrics are only available on socket and system level:
READ Memory read traffic on this socket in GB 23.108
WRITE Memory read traffic on this socket in GB 10.782
The following metrics are only available on a socket level:
Proc Energy (Joules) The energy consumed by the processor in Joules. Divide by the time to get the power consumption in watt 122.457
DRAM Energy (Joules) The energy consumed by the DRAM attached to this socket in Joules. Divide by the time to get the power consumption in watt 115.747
TEMP Thermal headroom in Kelvin (max design temperature – current temperature) 32
The following metrics are only available on a system level:
INST Number of instructions retired 119706
ACYC Number of clockticks, This takes turbo and power saving modes into account. 750640.8
TIME(ticks) Number of invariant clockticks. This is invariant to turbo and power saving modes. 2817.883
PhysIPC Instructions per cycle (IPC) multiplied by number of threads per core. See section "Core Cycles-per-Instruction (CPI) and Thread CPI" in Performance Insights to Intel® Hyper-Threading Technology for some background information. 0.319
PhysIPC% Instructions per cycle (IPC) multiplied by number of threads per core relative to maximum IPC 7.974
INSTnom Instructions per nominal cycle multiplied by number of threads per core 0.365
INSTnom% Instructions per nominal cycle multiplied by number of threads per core relative to maximum IPC. The maximum IPC is 2 for Atom and 4 for all other supported processors. 9.113
TotalQPIin QPI data traffic estimation (data traffic coming to CPU/socket through QPI links) in MB (1024*1024) 21937.96
QPItoMC Ratio of QPI traffic to memory traffic 0.632
TotalQPIout QPI traffic estimation (data and non-data traffic outgoing from CPU/socket through QPI links) in MB (1024*1024) 38443.3

Please also note that PCM reports absolute values for the measured time interval. For example, if you use a time interval of 5 seconds, memory traffic or instructions retired are reported for the whole 5 seconds. Only if you are executing PCM with 1 sec time interval, you will get memory traffic in GB/s.

 

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