CPU2017 Flag Description
Supermicro A+ Server 2014TP-HTR (H12SST-PS , AMD EPYC 7473X)

Compilers: AMD Optimizing C/C++ Compiler Suite


Base Compiler Invocation

C benchmarks

C++ benchmarks

Fortran benchmarks


Peak Compiler Invocation

C benchmarks

C++ benchmarks

Fortran benchmarks


Base Portability Flags

500.perlbench_r

502.gcc_r

505.mcf_r

520.omnetpp_r

523.xalancbmk_r

525.x264_r

531.deepsjeng_r

541.leela_r

548.exchange2_r

557.xz_r


Peak Portability Flags

500.perlbench_r

502.gcc_r

505.mcf_r

520.omnetpp_r

523.xalancbmk_r

525.x264_r

531.deepsjeng_r

541.leela_r

548.exchange2_r

557.xz_r


Base Optimization Flags

C benchmarks

C++ benchmarks

Fortran benchmarks


Peak Optimization Flags

C benchmarks

500.perlbench_r

502.gcc_r

505.mcf_r

525.x264_r

557.xz_r

C++ benchmarks

520.omnetpp_r

523.xalancbmk_r

531.deepsjeng_r

541.leela_r

Fortran benchmarks


Base Other Flags

C benchmarks

C++ benchmarks


Peak Other Flags

C benchmarks (except as noted below)

502.gcc_r

C++ benchmarks (except as noted below)

523.xalancbmk_r


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

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"


Shell, Environment, and Other Software Settings

Transparent Huge Pages (THP)

THP is an abstraction layer that automates most aspects of creating, managing, and using huge pages. It is designed to hide much of the complexity in using huge pages from system administrators and developers. Huge pages increase the memory page size from 4 kilobytes to 2 megabytes. This provides significant performance advantages on systems with highly contended resources and large memory workloads. If memory utilization is too high or memory is badly fragmented which prevents huge pages being allocated, the kernel will assign smaller 4k pages instead. Most recent Linux OS releases have THP enabled by default.

THP usage is controlled by the sysfs setting /sys/kernel/mm/transparent_hugepage/enabled. Possible values:

The SPEC CPU benchmark codes themselves never explicitly request huge pages, as the mechanism to do that is OS-specific and can change over time. Libraries such as jemalloc which are used by the benchmarks may explicitly request huge pages, and use of such libraries can make the "madvise" setting relevant and useful.

When no huge pages are immediately available and one is requested, how the system handles the request for THP creation is controlled by the sysfs setting /sys/kernel/mm/transparent_hugepage/defrag. Possible values:

An application that "always" requests THP often can benefit from waiting for an allocation until those huge pages can be assembled.
For more information see the Linux transparent hugepage documentation.

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 that indicates the location in the filesystem of bundled libraries to use when running the benchmark binaries.

kernel/numa_balancing

This OS setting controls automatic NUMA balancing on memory mapping and process placement. NUMA balancing incurs overhead for no benefit on workloads that are already bound to NUMA nodes.

Possible settings:

For more information see the numa_balancing entry in the Linux sysctl documentation.

kernel/randomize_va_space (ASLR)

This setting can be used to select the type of process address space randomization. Defaults differ based on whether the architecture supports ASLR, whether the kernel was built with the CONFIG_COMPAT_BRK option or not, or the kernel boot options used.

Possible settings:

Disabling ASLR can make process execution more deterministic and runtimes more consistent. For more information see the randomize_va_space entry in the Linux sysctl documentation.

MALLOC_CONF

The jemalloc library has tunable parameters, many of which may be changed at run-time via several mechanisms, one of which is the MALLOC_CONF environment variable. Other methods, as well as the order in which they're referenced, are detailed in the jemalloc documentation's TUNING section.

The options that can be tuned at run-time are everything in the jemalloc documentation's MALLCTL NAMESPACE section that begins with "opt.".

The options that may be encountered in SPEC CPU 2017 results are detailed here:

PGHPF_ZMEM

An environment variable used to initialize the allocated memory. Setting PGHPF_ZMEM to "Yes" has the effect of initializing all allocated memory to zero.

GOMP_CPU_AFFINITY

This environment variable is used to set the thread affinity for threads spawned by OpenMP.

OMP_DYNAMIC

This environment variable is defined as part of the OpenMP standard. Setting it to "false" prevents the OpenMP runtime from dynamically adjusting the number of threads to use for parallel execution.

For more information, see chapter 4 ("Environment Variables") in the OpenMP 4.5 Specification.

OMP_SCHEDULE

This environment variable is defined as part of the OpenMP standard. Setting it to "static" causes loop iterations to be assigned to threads in round-robin fashion in the order of the thread number.

For more information, see chapter 4 ("Environment Variables") in the OpenMP 4.5 Specification.

OMP_STACKSIZE

This environment variable is defined as part of the OpenMP standard and controls the size of the stack for threads created by OpenMP.

For more information, see chapter 4 ("Environment Variables") in the OpenMP 4.5 Specification.

OMP_THREAD_LIMIT

This environment variable is defined as part of the OpenMP standard and limits the maximum number of OpenMP threads that can be created.

For more information, see chapter 4 ("Environment Variables") in the OpenMP 4.5 Specification.

LIBOMP_NUM_HIDDEN_HELPER_THREADS

target nowait is supported via hidden helper task, which is a task not bound to any parallel region. A hidden helper team with a number of threads is created when the first hidden helper task is encountered.

The number of threads can be configured via the environment variable LIBOMP_NUM_HIDDEN_HELPER_THREADS. The default is 8. If LIBOMP_NUM_HIDDEN_HELPER_THREADS is 0, the hidden helper task is disabled and support falls back to a regular OpenMP task. The hidden helper task can also be disabled by setting the environment variable LIBOMP_USE_HIDDEN_HELPER_TASK=OFF.


Operating System Tuning Parameters

kernel.randomize_va_space (ASLR)
This setting can be used to select the type of process address space randomization. Defaults differ based on whether the architecture supports ASLR, whether the kernel was built with the CONFIG_COMPAT_BRK option or not, or the kernel boot options used.
Possible settings: Disabling ASLR can make process execution more deterministic and runtimes more consistent. For more information see the randomize_va_space entry in the Linux sysctl documentation.
Transparent Hugepages (THP)
THP is an abstraction layer that automates most aspects of creating, managing, and using huge pages. It is designed to hide much of the complexity in using huge pages from system administrators and developers. Huge pages increase the memory page size from 4 kilobytes to 2 megabytes. This provides significant performance advantages on systems with highly contended resources and large memory workloads. If memory utilization is too high or memory is badly fragmented which prevents hugepages being allocated, the kernel will assign smaller 4k pages instead. Most recent Linux OS releases have THP enabled by default.
THP usage is controlled by the sysfs setting /sys/kernel/mm/transparent_hugepage/enabled. Possible values: THP creation is controlled by the sysfs setting /sys/kernel/mm/transparent_hugepage/defrag. Possible values: An application that "always" requests THP often can benefit from waiting for an allocation until those huge pages can be assembled.
For more information see the Linux transparent hugepage documentation.

Firmware / BIOS / Microcode Settings

Determinism Control:
This BIOS option allows for choose AGESA determinism control. AGESA is an acronym for "AMD Generic Encapsulated Software Architecture." AGESA is a bootstrap protocol by which system devices on AMD64-architecture mainboards are initialized, it responsible for the initialization of the processor cores, memory, and the HyperTransport controller. Available settings are:
Determinism Slider:
This BIOS option allows for Enable/Disable AGESA determinism to control performance. AGESA is an acronym for "AMD Generic Encapsulated Software Architecture." AGESA is a bootstrap protocol by which system devices on AMD64-architecture mainboards are initialized, it responsible for the initialization of the processor cores, memory, and the HyperTransport controller. Available settings are:
cTDP Control:
This BIOS option is for "Configurable TDP (cTDP)", it allows user can set customized value for TDP. Available settings are:
cTDP:
TDP is an acronym for “Thermal Design Power.” TDP is the recommended target for power used when designing the cooling capacity for a server. EPYC processors are able to control this target power consumption within certain limits. This capability is referred to as “configurable TDP” or "cTDP." cTDP can be used to reduce power consumption for greater efficiency, or in some cases, increase power consumption above the default value to provide additional performance. cTDP is controlled using a BIOS option.

The default EPYC cTDP value corresponds with the microprocessor’s nominal TDP. For the EPYC 7413, the default value is 180W. The default cTDP value is set at a good balance between performance and energy efficiency. The EPYC 7413 cTDP can be reduced as low as 165W, which will minimize the power consumption for the processor under load, but at the expense of peak performance. Increasing the EPYC 7713 cTDP to 240W will maximize peak performance by allowing the CPU to maintain higher dynamic clock speeds, but will make the microprocessor less energy efficient. Note that at maximum cTDP, the CPU thermal solution must be capable of dissipating at least 240W or the EPYC 7713 processor might engage in thermal throttling under load.

The available cTDP ranges for each EPYC model are in the table below:
ModelNominal TDP Minimum cTDP Maximum cTDP**
EPYC 7773X280W 225W 280W
EPYC 7573X280W 225W 280W
EPYC 7473X240W 225W 280W
EPYC 7373X240W 225W 280W
EPYC 7763280W 225W 280W
EPYC 7713225W 225W 240W
EPYC 7713P225W 225W 240W
EPYC 7663240W 225W 240W
EPYC 7643225W 225W 240W
EPYC 75F3280W 225W 280W
EPYC 7543225W 225W 240W
EPYC 7543P225W 225W 240W
EPYC 7513200W 165W 200W
EPYC 7453225W 225W 240W
EPYC 74F3240W 225W 240W
EPYC 7443200W 165W 200W
EPYC 7443P200W 165W 200W
EPYC 7413180W 165W 200W
EPYC 73F3224W 225W 240W
EPYC 7343195W 165W 200W
EPYC 7313155W 155W 180W
EPYC 7313P155W 155W 180W
EPYC 72F3180W 165W 200W
* cTDP must remain below the thermal solution design parameters or thermal throttling could be frequently encountered.
IOMMU:
The I/O Memory Management Unit (IOMMU) extends the AMD64 system architecture by adding support for address translation and system memory access protection on DMA transfers from periph-eral devices. IOMMU also helps filter and remap interrupts from peripheral devices. Available settings are:
Package Power Limit Control:
This is a per processor Package Power Limit (PPT) value applicable for all populated processors in the system. This can be set to limit the PPT to a certain value. Available settings are:
Package Power Limit:
Set customize processor Package Power Limit (PPT) value to be used on all populated processors in the system. If set to 240 = Use the 240W PPT ***PPT will be used as the ASIC power limit***
APBDIS:
APBDis is an IO Boost disable on uncore. For any system user that needs to block these uncore optimizations that are impacting base core clock speed, we are exposing a method to disable this behavior called APBDis. This locks the fabric clock to the non-boosted speeds. Available settings are:
NUMA Nodes Per Socket:
Specifies the number of desired NUMA nodes per socket. This option allows the user to divide the memory that each socket has into a certain number of NUMA memory nodes for optimal memory bandwidth. Available settings are:

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/aocc320-flags-A1.html,
http://www.spec.org/cpu2017/flags/Supermicro-Platform-Settings-V1.2-Milan-revD.html.

You can also download the XML flags sources by saving the following links:
http://www.spec.org/cpu2017/flags/aocc320-flags-A1.xml,
http://www.spec.org/cpu2017/flags/Supermicro-Platform-Settings-V1.2-Milan-revD.xml.


For questions about the meanings of these flags, please contact the tester.
For other inquiries, please contact info@spec.org
Copyright 2017-2022 Standard Performance Evaluation Corporation
Tested with SPEC CPU2017 v1.1.8.
Report generated on 2022-03-22 10:59:06 by SPEC CPU2017 flags formatter v5178.