CPU2006 Flag Description
IBM Corporation IBM System x3450 (Intel Xeon X5482)

Copyright © 2006 Intel Corporation. All Rights Reserved.


Base Compiler Invocation

C benchmarks

C++ benchmarks

Fortran benchmarks

Benchmarks using both Fortran and C


Peak Compiler Invocation

C benchmarks (except as noted below)

482.sphinx3

C++ benchmarks (except as noted below)

450.soplex

Fortran benchmarks

Benchmarks using both Fortran and C


Base Portability Flags

410.bwaves

416.gamess

433.milc

434.zeusmp

435.gromacs

436.cactusADM

437.leslie3d

444.namd

447.dealII

450.soplex

453.povray

454.calculix

459.GemsFDTD

465.tonto

470.lbm

481.wrf

482.sphinx3


Peak Portability Flags

410.bwaves

416.gamess

433.milc

434.zeusmp

435.gromacs

436.cactusADM

437.leslie3d

444.namd

447.dealII

453.povray

454.calculix

459.GemsFDTD

465.tonto

470.lbm

481.wrf


Base Optimization Flags

C benchmarks

C++ benchmarks

Fortran benchmarks

Benchmarks using both Fortran and C


Peak Optimization Flags

C benchmarks

433.milc

470.lbm

482.sphinx3

C++ benchmarks

444.namd

447.dealII

450.soplex

453.povray

Fortran benchmarks

410.bwaves

416.gamess

434.zeusmp

437.leslie3d

459.GemsFDTD

465.tonto

Benchmarks using both Fortran and C

435.gromacs

436.cactusADM

454.calculix

481.wrf


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.


System and Other Tuning Information

Platform settings

One or more of the following settings may have been set. If so, the "General Notes" section of the report will say so; and you can read below to find out more about what these settings mean.

KMP_STACKSIZE

Specify stack size to be allocated for each thread.

KMP_AFFINITY

KMP_AFFINITY = < physical | logical >, starting-core-id
specifies the static mapping of user threads to physical cores. For example, if you have a system configured with 8 cores, OMP_NUM_THREADS=8 and KMP_AFFINITY=physical,0 then thread 0 will mapped to core 0, thread 1 will be mapped to core 1, and so on in a round-robin fashion.

OMP_NUM_THREADS

Sets the maximum number of threads to use for OpenMP* parallel regions if no other value is specified in the application. This environment variable applies to both -openmp and -parallel (Linux and Mac OS X) or /Qopenmp and /Qparallel (Windows). Example syntax on a Linux system with 8 cores: export OMP_NUM_THREADS=8

Hardware Prefetch:

This BIOS option allows the enabling/disabling of a processor mechanism to prefetch data into the cache according to a pattern-recognition algorithm.

In some cases, setting this option to Disabled may improve performance. Users should only disable this option after performing application benchmarking to verify improved performance in their environment.

Adjacent Sector Prefetch:

This BIOS option allows the enabling/disabling of a processor mechanism to fetch the adjacent cache line within an 128-byte sector that contains the data needed due to a cache line miss.

In some cases, setting this option to Disabled may improve performance. Users should only disable this option after performing application benchmarking to verify improved performance in their environment.

High Bandwidth:

Enabling this option allows the chipset to defer memory transactions and process them out of order for optimal performance.

powersaved off:

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

ulimit -s <n>

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

submit= MYMASK=`printf '0x%x' $((1<<$SPECCOPYNUM))`; /usr/bin/taskset $MYMASK $command

When running multiple copies of benchmarks, the SPEC config file feature submit is sometimes used to cause individual jobs to be bound to specific processors. This specific submit command is used for Linux. The description of the elements of the command are:

submit= $[top]/mysubmit.pl $SPECCOPYNUM "$command"

On Xeon 74xx series processors, some benchmarks at peak will run n/2 copies on a system with n logical processors. The mysubmit.pl script assigns each copy in such a way that no two copies will share an L2 cache, for optimal performance. The script looks in /proc/cpuinfo to come up with the list of cores that will satisfy this requirement. The source code is shown below.