CPU2017 Flag Description
Dell Inc. PowerEdge R6415 (AMD EPYC 7551P, 2.00GHz)

This result has been formatted using multiple flags files. The "default header section" from each of them appears next.


Default header section from aocc100-flags-revC-I

AMD Optimizing C/C++ Compiler Suite SPEC CPU2017 Flag Description

Compilers: AOCC Suite


Default header section from gcc

GNU Compiler Collection Flags

Flag descriptions for GCC, the GNU Compiler Collection

Note: The GNU Compiler Collection provides a wide array of compiler options, described in detail and readily available at https://gcc.gnu.org/onlinedocs/gcc/Option-Index.html#Option-Index and https://gcc.gnu.org/onlinedocs/gfortran/. This SPEC CPU flags file contains excerpts from and brief summaries of portions of that documentation.

SPEC's modifications are:
Copyright (C) 2006-2017 Standard Performance Evaluation Corporation

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with the Invariant Sections being "Funding Free Software", the Front-Cover Texts being (a) (see below), and with the Back-Cover Texts being (b) (see below). A copy of the license is included in your SPEC CPU kit at $SPEC/Docs/licenses/FDL.v1.3 and on the web at http://www.spec.org/cpu2017/Docs/licenses/FDL.v1.3. A copy of "Funding Free Software" is on your SPEC CPU kit at $SPEC/Docs/licenses/FundingFreeSW and on the web at http://www.spec.org/cpu2017/Docs/licenses/FundingFreeSW.

(a) The FSF's Front-Cover Text is:

A GNU Manual

(b) The FSF's Back-Cover Text is:

You have freedom to copy and modify this GNU Manual, like GNU software. Copies published by the Free Software Foundation raise funds for GNU development.


Base Compiler Invocation

C benchmarks

C++ benchmarks

Fortran benchmarks

Benchmarks using both Fortran and C

Benchmarks using both C and C++

Benchmarks using Fortran, C, and C++


Peak Compiler Invocation

C benchmarks

C++ benchmarks

Fortran benchmarks

Benchmarks using both Fortran and C

Benchmarks using both C and C++

Benchmarks using Fortran, C, and C++


Base Portability Flags

503.bwaves_r

507.cactuBSSN_r

508.namd_r

510.parest_r

511.povray_r

519.lbm_r

521.wrf_r

526.blender_r

527.cam4_r

538.imagick_r

544.nab_r

549.fotonik3d_r

554.roms_r


Peak Portability Flags

503.bwaves_r

507.cactuBSSN_r

508.namd_r

510.parest_r

511.povray_r

519.lbm_r

521.wrf_r

526.blender_r

527.cam4_r

538.imagick_r

544.nab_r

549.fotonik3d_r

554.roms_r


Base Optimization Flags

C benchmarks

C++ benchmarks

Fortran benchmarks

Benchmarks using both Fortran and C

Benchmarks using both C and C++

Benchmarks using Fortran, C, and C++


Peak Optimization Flags

C benchmarks

C++ benchmarks

Fortran benchmarks

Benchmarks using both Fortran and C

521.wrf_r

527.cam4_r

Benchmarks using both C and C++

Benchmarks using Fortran, C, and C++


Implicitly Included Flags

This section contains descriptions of flags that were included implicitly by other flags, but which do not have a permanent home at SPEC.


Commands and Options Used to Submit Benchmark Runs

This result has been formatted using multiple flags files. The "submit command" from each of them appears next.


Submit command from aocc100-flags-revC-I

AMD Optimizing C/C++ Compiler Suite SPEC CPU2017 Flag Description

Using numactl to bind processes and memory to cores

For multi-copy runs or single copy runs on systems with multiple sockets, it is advantageous to bind a process to a particular core. Otherwise, the OS may arbitrarily move your process from one core to another. This can affect performance. To help, SPEC allows the use of a "submit" command where users can specify a utility to use to bind processes. We have found the utility 'numactl' to be the best choice.

numactl runs processes with a specific NUMA scheduling or memory placement policy. The policy is set for a command and inherited by all of its children. The numactl flag "--physcpubind" specifies which core(s) to bind the process. "-l" instructs numactl to keep a process's memory on the local node while "-m" specifies which node(s) to place a process's memory. For full details on using numactl, please refer to your Linux documentation, 'man numactl'

Note that some older versions of numactl incorrectly interpret application arguments as its own. For example, with the command "numactl --physcpubind=0 -l a.out -m a", numactl will interpret a.out's "-m" option as its own "-m" option. To work around this problem, we put the command to be run in a shell script and then run the shell script using numactl. For example: "echo 'a.out -m a' > run.sh ; numactl --physcpubind=0 bash run.sh"


Submit command from gcc

GNU Compiler Collection Flags

SPECrate runs might use one of these methods to bind processes to specific processors, depending on the config file.


Commands and Options Used for Feedback-Directed Optimization

No special commands are needed for feedback-directed optimization, other than the compiler profile  flags.


Shell, Environment, and Other Software Settings

This result has been formatted using multiple flags files. The "sw environment" from each of them appears next.


Sw environment from aocc100-flags-revC-I

AMD Optimizing C/C++ Compiler Suite SPEC CPU2017 Flag Description

Transparent Huge Pages (THP)

THP is an abstraction layer that automates most aspects of creating, managing, and using huge pages. THP is designed to hide much of the complexity in using huge pages from system administrators and developers, as normal huge pages must be assigned at boot time, can be difficult to manage manually, and often require significant changes to code in order to be used effectively. Most recent Linux OS releases have THP enabled by default.

Linux Huge Page settings

If you need finer control you can manually set huge pages using the following steps:

Note that further information about huge pages may be found in the Linux kernel documentation file hugetlbpage.txt.

ulimit -s <n>

Sets the stack size to n kbytes, or unlimited to allow the stack size to grow without limit.

ulimit -l <n>

Sets the maximum size of memory that may be locked into physical memory.

powersave -f (on SuSE)

Makes the powersave daemon set the CPUs to the highest supported frequency.

/etc/init.d/cpuspeed stop (on Red Hat)

Disables the cpu frequency scaling program in order to set the CPUs to the highest supported frequency.

LD_LIBRARY_PATH

An environment variable set to include the LLVM, JEMalloc and SmartHeap libraries used during compilation of the binaries. This environment variable setting is not needed when building the binaries on the system under test.

kernel/randomize_va_space

This option can be used to select the type of process address space randomization that is used in the system, for architectures that support this feature.

MALLOC_CONF

An environment variable set to tune the jemalloc allocation strategy during the execution of the binaries. This environment variable setting is not needed when building the binaries on the system under test.


Sw environment from gcc

GNU Compiler Collection Flags

One or more of the following may have been used in the run. If so, it will be listed in the notes sections. Here is a brief guide to understanding them:


Flag description origin markings:

[user] Indicates that the flag description came from the user flags file.
[suite] Indicates that the flag description came from the suite-wide flags file.
[benchmark] Indicates that the flag description came from a per-benchmark flags file.

The flags files that were used to format this result can be browsed at
http://www.spec.org/cpu2017/flags/aocc100-flags-revC-I.2018-11-13.html,
http://www.spec.org/cpu2017/flags/gcc.2018-02-16.html.

You can also download the XML flags sources by saving the following links:
http://www.spec.org/cpu2017/flags/aocc100-flags-revC-I.2018-11-13.xml,
http://www.spec.org/cpu2017/flags/gcc.2018-02-16.xml.


For questions about the meanings of these flags, please contact the tester.
For other inquiries, please contact info@spec.org
Copyright 2017-2018 Standard Performance Evaluation Corporation
Tested with SPEC CPU2017 v1.0.5.
Report generated on 2018-12-26 13:01:52 by SPEC CPU2017 flags formatter v5178.