Developer Guide

  • 2021.3
  • 11/18/2021
  • Public
Contents

Command-Line Options

Running the MRL sample workload with the
-h
option yields the following usage message:
Usage: taskset --cpu-list 3 mrl_userspace_app --address ADDRESS --iterations ITERATIONS --processor {TGL-U,TGL-H,EHL} [--outliers OUTLIERS] [--threshold THRESHOLD]
Option
Description
taskset --cpu-list 3
Processor core on which the sample will run.
--address ADDRESS
Physical memory address of the PCIe device with
0x
prefix. Example: 0x607d4dc000.
--iterations ITERATIONS
Execute N iterations of the main loop to gather more precise timing statistics.
--processor PROCESSOR
Processor where the MRL application will be executed.
--outliers OUTLIERS
Optional. This parameter is used to filter iterations that executed greater than N instructions. By default, N is set to the expected amount of instructions for measuring latency of a single MMIO read transaction. By removing iterations with instructions greater than N, MRL is effectively masking interrupts and software overhead. (default: 90)
--threshold THRESHOLD
Optional. The MRL sample can hang due to a low outliers number. If
--outliers N
is too small, the sample will never count any iterations and will never stop running because it is waiting to collect N data points as specified in
--iterations
. To avoid the hang, use the threshold parameter to limit the number of iterations N that the sample should run. This parameter will stop the sample after it has run N iterations. (default: equal to 120% of
--iterations N
)
To get the physical memory address of the PCIe device, run the following commands on each board:
lspci | grep -E 'Ethernet controller: Intel Corporation'
The following output example shows the PCIe device name is aa:00.0.
aa:00.0 Ethernet controller: Intel Corporation Device 15f2 (rev 20)
If you see
15f2
in the output, the device is an Intel® Ethernet Controller I225. If you see
a0ac
,
43ac
or
4b32
in the output, the device is an integrated TSN Ethernet controller.
Run
lspci
with found PCIe device address and search for device memory.
lspci -s aa:00.0 -v | grep Memory
The following output example shows the addresses 88200000 and 88300000.
Memory at 88200000 (32-bit, non-prefetchable) [size=1M] Memory at 88300000 (32-bit, non-prefetchable) [size=16K]
Enter the address in the
--address
field with
0x
prefix.

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.