CPU2006 Flag Description
ACTION S.A. ACTINA SOLAR E 110 X3 (Intel Xeon X3330, 2.66 GHz)
Copyright © 2006 Intel Corporation. All Rights Reserved.
Base Portability Flags
-
- -DSPEC_CPU_LP64
![[suite]](http://www.spec.org/auto/cpu2006/flags/suite.png)
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -nofor_main
![[user]](http://www.spec.org/auto/cpu2006/flags/user.png)
- LDPORTABILITY
-
This option specifies that the main program is not written in Fortran.
It is a link-time option that prevents the compiler from linking for_main.o
into applications.
For example, if the main program is written in C and calls a Fortran subprogram,
specify -nofor-main when compiling the program with the ifort command.
If you omit this option, the main program must be a Fortran program.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -nofor_main
- LDPORTABILITY
-
This option specifies that the main program is not written in Fortran.
It is a link-time option that prevents the compiler from linking for_main.o
into applications.
For example, if the main program is written in C and calls a Fortran subprogram,
specify -nofor-main when compiling the program with the ifort command.
If you omit this option, the main program must be a Fortran program.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -nofor_main
- LDPORTABILITY
-
This option specifies that the main program is not written in Fortran.
It is a link-time option that prevents the compiler from linking for_main.o
into applications.
For example, if the main program is written in C and calls a Fortran subprogram,
specify -nofor-main when compiling the program with the ifort command.
If you omit this option, the main program must be a Fortran program.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
-
-
-
- -DSPEC_CPU_LP64
- PORTABILITY
-
This option is used to indicate that the host system's integers are 32-bits
wide, and longs and pointers are 64-bits wide. Not all benchmarks
recognize this macro, but the preferred practice for data model selection
applies the flags to all benchmarks; this flag description is a placeholder
for those benchmarks that do not recognize this macro.
Base Optimization Flags
-
- -xSSE4.1
- OPTIMIZE
-
Code is optimized for Intel(R) processors with support for SSE 4.1 instructions.
The resulting code may contain unconditional use of features that are not supported
on other processors. This option also enables new optimizations in addition to
Intel processor-specific optimizations including advanced data layout and code
restructuring optimizations to improve memory accesses for Intel processors.
Do not use this option if you are executing a program on a processor that
is not an Intel processor. If you use this option on a non-compatible processor
to compile the main program (in Fortran) or the function main() in C/C++, the
program will display a fatal run-time error if they are executed on unsupported
processors.
-
-
- -O3
- OPTIMIZE
-
Enables O2 optimizations plus more aggressive optimizations,
such as prefetching, scalar replacement, and loop and memory
access transformations. Enables optimizations for maximum speed,
such as:
- Loop unrolling, including instruction scheduling
- Code replication to eliminate branches
- Padding the size of certain power-of-two arrays to allow
more efficient cache use.
On IA-32 and Intel EM64T processors, when O3 is used with options
-ax or -x (Linux) or with options /Qax or /Qx (Windows), the compiler
performs more aggressive data dependency analysis than for O2, which
may result in longer compilation times.
The O3 optimizations may not cause higher performance unless loop and
memory access transformations take place. The optimizations may slow
down code in some cases compared to O2 optimizations.
The O3 option is recommended for applications that have loops that heavily
use floating-point calculations and process large data sets.
- Includes:
-
- -no-prec-div
- OPTIMIZE
-
(disable/enable[default] -prec-div)
-no-prec-div enables optimizations that give slightly less precise results
than full IEEE division.
When you specify -no-prec-div along with some optimizations, such as
-xN and -xB (Linux) or /QxN and /QxB (Windows),
the compiler may change floating-point division computations into
multiplication by the reciprocal of the denominator.
For example, A/B is computed as A * (1/B) to improve the speed of the
computation.
However, sometimes the value produced by this transformation is
not as accurate as full IEEE division. When it is important to have fully
precise IEEE division, do not use -no-prec-div.
This will enable the default -prec-div and the result will be more accurate,
with some loss of performance.
-
-
-
- -xSSE4.1
- OPTIMIZE
-
Code is optimized for Intel(R) processors with support for SSE 4.1 instructions.
The resulting code may contain unconditional use of features that are not supported
on other processors. This option also enables new optimizations in addition to
Intel processor-specific optimizations including advanced data layout and code
restructuring optimizations to improve memory accesses for Intel processors.
Do not use this option if you are executing a program on a processor that
is not an Intel processor. If you use this option on a non-compatible processor
to compile the main program (in Fortran) or the function main() in C/C++, the
program will display a fatal run-time error if they are executed on unsupported
processors.
-
-
- -O3
- OPTIMIZE
-
Enables O2 optimizations plus more aggressive optimizations,
such as prefetching, scalar replacement, and loop and memory
access transformations. Enables optimizations for maximum speed,
such as:
- Loop unrolling, including instruction scheduling
- Code replication to eliminate branches
- Padding the size of certain power-of-two arrays to allow
more efficient cache use.
On IA-32 and Intel EM64T processors, when O3 is used with options
-ax or -x (Linux) or with options /Qax or /Qx (Windows), the compiler
performs more aggressive data dependency analysis than for O2, which
may result in longer compilation times.
The O3 optimizations may not cause higher performance unless loop and
memory access transformations take place. The optimizations may slow
down code in some cases compared to O2 optimizations.
The O3 option is recommended for applications that have loops that heavily
use floating-point calculations and process large data sets.
- Includes:
-
- -no-prec-div
- OPTIMIZE
-
(disable/enable[default] -prec-div)
-no-prec-div enables optimizations that give slightly less precise results
than full IEEE division.
When you specify -no-prec-div along with some optimizations, such as
-xN and -xB (Linux) or /QxN and /QxB (Windows),
the compiler may change floating-point division computations into
multiplication by the reciprocal of the denominator.
For example, A/B is computed as A * (1/B) to improve the speed of the
computation.
However, sometimes the value produced by this transformation is
not as accurate as full IEEE division. When it is important to have fully
precise IEEE division, do not use -no-prec-div.
This will enable the default -prec-div and the result will be more accurate,
with some loss of performance.
-
-
-
- -xSSE4.1
- OPTIMIZE
-
Code is optimized for Intel(R) processors with support for SSE 4.1 instructions.
The resulting code may contain unconditional use of features that are not supported
on other processors. This option also enables new optimizations in addition to
Intel processor-specific optimizations including advanced data layout and code
restructuring optimizations to improve memory accesses for Intel processors.
Do not use this option if you are executing a program on a processor that
is not an Intel processor. If you use this option on a non-compatible processor
to compile the main program (in Fortran) or the function main() in C/C++, the
program will display a fatal run-time error if they are executed on unsupported
processors.
-
-
- -O3
- OPTIMIZE
-
Enables O2 optimizations plus more aggressive optimizations,
such as prefetching, scalar replacement, and loop and memory
access transformations. Enables optimizations for maximum speed,
such as:
- Loop unrolling, including instruction scheduling
- Code replication to eliminate branches
- Padding the size of certain power-of-two arrays to allow
more efficient cache use.
On IA-32 and Intel EM64T processors, when O3 is used with options
-ax or -x (Linux) or with options /Qax or /Qx (Windows), the compiler
performs more aggressive data dependency analysis than for O2, which
may result in longer compilation times.
The O3 optimizations may not cause higher performance unless loop and
memory access transformations take place. The optimizations may slow
down code in some cases compared to O2 optimizations.
The O3 option is recommended for applications that have loops that heavily
use floating-point calculations and process large data sets.
- Includes:
-
- -no-prec-div
- OPTIMIZE
-
(disable/enable[default] -prec-div)
-no-prec-div enables optimizations that give slightly less precise results
than full IEEE division.
When you specify -no-prec-div along with some optimizations, such as
-xN and -xB (Linux) or /QxN and /QxB (Windows),
the compiler may change floating-point division computations into
multiplication by the reciprocal of the denominator.
For example, A/B is computed as A * (1/B) to improve the speed of the
computation.
However, sometimes the value produced by this transformation is
not as accurate as full IEEE division. When it is important to have fully
precise IEEE division, do not use -no-prec-div.
This will enable the default -prec-div and the result will be more accurate,
with some loss of performance.
-
-
-
- -xSSE4.1
- OPTIMIZE
-
Code is optimized for Intel(R) processors with support for SSE 4.1 instructions.
The resulting code may contain unconditional use of features that are not supported
on other processors. This option also enables new optimizations in addition to
Intel processor-specific optimizations including advanced data layout and code
restructuring optimizations to improve memory accesses for Intel processors.
Do not use this option if you are executing a program on a processor that
is not an Intel processor. If you use this option on a non-compatible processor
to compile the main program (in Fortran) or the function main() in C/C++, the
program will display a fatal run-time error if they are executed on unsupported
processors.
-
-
- -O3
- OPTIMIZE
-
Enables O2 optimizations plus more aggressive optimizations,
such as prefetching, scalar replacement, and loop and memory
access transformations. Enables optimizations for maximum speed,
such as:
- Loop unrolling, including instruction scheduling
- Code replication to eliminate branches
- Padding the size of certain power-of-two arrays to allow
more efficient cache use.
On IA-32 and Intel EM64T processors, when O3 is used with options
-ax or -x (Linux) or with options /Qax or /Qx (Windows), the compiler
performs more aggressive data dependency analysis than for O2, which
may result in longer compilation times.
The O3 optimizations may not cause higher performance unless loop and
memory access transformations take place. The optimizations may slow
down code in some cases compared to O2 optimizations.
The O3 option is recommended for applications that have loops that heavily
use floating-point calculations and process large data sets.
- Includes:
-
- -no-prec-div
- OPTIMIZE
-
(disable/enable[default] -prec-div)
-no-prec-div enables optimizations that give slightly less precise results
than full IEEE division.
When you specify -no-prec-div along with some optimizations, such as
-xN and -xB (Linux) or /QxN and /QxB (Windows),
the compiler may change floating-point division computations into
multiplication by the reciprocal of the denominator.
For example, A/B is computed as A * (1/B) to improve the speed of the
computation.
However, sometimes the value produced by this transformation is
not as accurate as full IEEE division. When it is important to have fully
precise IEEE division, do not use -no-prec-div.
This will enable the default -prec-div and the result will be more accurate,
with some loss of performance.
-
-
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.
-
- -O2
-
Enables optimizations for speed. This is the generally recommended
optimization level. This option also enables:
- Inlining of intrinsics
- Intra-file interprocedural optimizations, which include:
- inlining
- constant propagation
- forward substitution
- routine attribute propagation
- variable address-taken analysis
- dead static function elimination
- removal of unreferenced variables
- The following capabilities for performance gain:
- constant propagation
- copy propagation
- dead-code elimination
- global register allocation
- global instruction scheduling and control speculation
- loop unrolling
- optimized code selection
- partial redundancy elimination
- strength reduction/induction variable simplification
- variable renaming
- exception handling optimizations
- tail recursions
- peephole optimizations
- structure assignment lowering and optimizations
- dead store elimination
- Includes:
-
- -O1
-
Enables optimizations for speed and disables some optimizations that increase code size and affect speed.
To limit code size, this option:
- Enables global optimization; this includes data-flow analysis,
code motion, strength reduction and test replacement, split-lifetime
analysis, and instruction scheduling.
- Disables intrinsic recognition and intrinsics inlining.
The O1 option may improve performance for applications with very large
code size, many branches, and execution time not dominated by code within loops.
-O1 sets the following options:
-funroll-loops0, -fno-builtin, -mno-ieee-fp, -fomit-framepointer, -ffunction-sections, -ftz
- Includes:
-
-
-
-
-
-
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.
Performance Optimized:
This BIOS option allows the user to set the memory at the rated speed.
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:
- /usr/bin/taskset [options] [mask] [pid | command [arg] ... ]:
taskset is used to set or retreive the CPU affinity of a running
process given its PID or to launch a new COMMAND with a given CPU
affinity. The CPU affinity is represented as a bitmask, with the
lowest order bit corresponding to the first logical CPU and highest
order bit corresponding to the last logical CPU. When the taskset
returns, it is guaranteed that the given program has been scheduled
to a legal CPU.
The default behaviour of taskset is to run a new command with a
given affinity mask:
taskset [mask] [command] [arguments]
- $MYMASK: The bitmask (in hexadecimal) corresponding to a specific
SPECCOPYNUM. For example, $MYMASK value for the first copy of a
rate run will be 0x00000001, for the second copy of the rate will
be 0x00000002 etc. Thus, the first copy of the rate run will have a
CPU affinity of CPU0, the second copy will have the affinity CPU1
etc.
- $command: Program to be started, in this case, the benchmark instance
to be started.
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.
Source
******************************************************************************************************
#!/usr/bin/perl
use strict;
use Cwd;
# The order in which we want copies to be bound to cores
# Copies: 0, 1, 2, 3
# Cores: 0, 1, 3, 6
my $rundir = getcwd;
my $copynum = shift @ARGV;
my $i;
my $j;
my $tag;
my $num;
my $core;
my $numofcores;
my @proc;
my @cores;
open(INPUT, "/proc/cpuinfo") or
die "can't open /proc/cpuinfo\n";
#open(OUTPUT, "STDOUT");
# proc[i][0] = logical processor ID
# proc[i][1] = physical processor ID
# proc[i][2] = core ID
$i = 0;
$numofcores = 0;
while(<INPUT>)
{
chop;
($tag, $num) = split(/\s+:\s+/, $_);
if ($tag eq "processor") {
$proc[$i][0] = $num;
}
if ($tag eq "physical id") {
$proc[$i][1] = $num;
}
if ($tag eq "core id") {
$proc[$i][2] = $num;
$i++;
$numofcores++;
}
}
$i = 0;
$j = 0;
for $core (0, 4, 2, 1, 5, 3) {
while ($i < $numofcores) {
if ($proc[$i][2] == $core) {
$cores[$j] = $proc[$i][0];
$j++;
}
$i++;
}
$i=0;
}
open RUNCOMMAND, "> runcommand" or die "failed to create run file";
print RUNCOMMAND "cd $rundir\n";
print RUNCOMMAND "@ARGV\n";
close RUNCOMMAND;
system 'taskset', '-c', $cores[$copynum], 'sh', "$rundir/runcommand";
For questions about the meanings of these flags, please contact the tester.
For other inquiries, please contact webmaster@spec.org
Copyright 2006-2014 Standard Performance Evaluation Corporation
Tested with SPEC CPU2006 v1.1.
Report generated on Tue Jul 22 22:22:51 2014 by SPEC CPU2006 flags formatter v6906.
![[benchmark]](http://www.spec.org/auto/cpu2006/flags/benchmark.png)