FLAG DESCRIPTIONS SUN C AND FORTRAN Forte[tm] Developer 7 Early Access 2 12/19/01 Compiler Flags Flag Description -autopar Perform automatic loop parallelization. -D Set definition for preprocessor. -dalign Assume double-type data is double aligned. -dn Specify static binding. -e Accept extended (132 character) input source lines (FORTRAN). -fast This is a convenience option for selecting a set of optimizations for performance, and it chooses: o The -native best machine characteristics option (-xarch=native, -xchip=native, -xcache=native) o Optimization level: -xO5 o A set of inline expansion templates (-libmil) o The -fsimple=2 option o The -dalign option o The -xalias_level=basic option (C only) o The -xlibmopt option o The -xdepend option o The -xprefetch option o The -xprefetch_level option o Options to turn off all trapping (-fns -ftrap=%none) o The -xvector option (Fortran only) o The -xpad option (Fortran only) -fixed Accept fixed-format input source files (FORTRAN). -fns Select non-standard floating point mode. This flag causes the nonstandard floating point mode to be enabled when a program begins execution. By default, the nonstandard floating point mode will not be enabled automatically. On some SPARC systems, the nonstandard floating point mode disables "gradual underflow", causing tiny results to be flushed to zero rather than producing subnormal numbers. It also causes subnormal operands to be silently replaced by zero. On those SPARC systems that do not support gradual underflow and subnormal numbers in hardware, use of this option can significantly improve the performance of some programs. Warning: When nonstandard mode is enabled, floating point arithmetic may produce results that do not con- form to the requirements of the IEEE 754 standard. See the Numerical Computation Guide for more information. -fsimple=0 Permits no simplifying assumptions. Preserves strict IEEE 754 conformance. -fsimple=1 With -fsimple=1, the optimizer can assume the following: o The IEEE 754 default rounding/trapping modes do not change after process initialization. o Computations producing no visible result other than potential floating-point exceptions may be deleted. o Computations with Infinity or NaNs as operands need not propagate NaNs to their results. For example, x*0 may be replaced by 0. o Computations do not depend on sign of zero. -fsimple=2 Permits aggressive floating point optimizations that may cause programs to produce different numeric results due to changes in rounding. Even with -fsimple=2, the optimizer still is not permitted to introduce a floating point exception in a program that otherwise produces none. -fsimple[=n] Allows the compiler to make simplifying assumptions concerning floating-point arithmetic. -ftrap=t Sets the IEEE 754 trapping mode in effect at startup. t is a comma-separated list that consists of one or more of the following: %all, %none, common, [no%]invalid, [no%]overflow, [no%]underflow, [no%]division, [no%]inexact. The default is -ftrap=%none. This option sets the IEEE 754 trapping modes that are established at program initialization. Processing is left-to-right. The common exceptions, by definition, are invalid, division by zero, and overflow. o %none, the default, turns off all trapping modes. Do not use this option for programs that depend on IEEE standard exception handling; you can get different numerical results, premature program termination, or unexpected SIGFPE signals. -libmil Use inline expansion templates for libm. -lm Link with math library -lmopt This chooses the math library that is optimized for speed -lmtmalloc fast concurrent malloc library suitable for multi-threaded applications -native Select native machine characteristics for optimization. -openmp enable explicit parallelization with Fortran 90 OpenMP directives. -pad Synonymous with -xpad (see -xpad below) -Qoption Pass flags along to compiler phase: f90comp Fortran first pass iropt Global optimizer cg Code generator -Qoption iropt See -W2, below. -Qoption iropt -Apf:const Mark prefetch candidates with detailed analysis of constants in array subscripts. -Qoption iropt -Apf:largedim Mark prefetch candidates by assuming a large first-dimension size for all arrays with unknown sizes at compile time. -Qoption iropt -Athr Perform tree height reduction optimizations. -Qoption iropt -whole Do whole program optimizations. -stackvar Allocate routine local variables on stack (FORTRAN). -W, Pass flags along to compiler phase (2=optimizer, c=code generator) -W2,-Ainline:call_in_pragma Consider functions called in parallel regions and loops as candidates for inlining -Xa Assume ANSI C conformance, allow K & R extensions. (default mode) -xalias_level= Allows compiler to perform type-based alias analysis at the given alias level (C). basic assume ISO C9X aliasing rules for basic types only. std assume ISO C9X aliasing rules. strong assume all pointers are type safe (strongly typed). -xarch= Limit the set of instructions the compiler may use. -Xc Assume strict ANSI C conformance. -xcache= Defines the cache properties for use by the optimizer. c must be one of the following: o native (set parameters for the host environment) o s1/l1/a1 o s1/l1/a1:s2/l2/a2 o s1/l1/a1:s2/l2/a2:s3/l3/a3 The si/li/ai are defined as follows: si The size of the data cache at level i, in kilobytes. li The line size of the data cache at level i, in bytes. ai The associativity of the data cache at level i. -xchip= Specifies the target processor for use by the optimizer. c must be one of: generic, generic64, native, native64, old, super, super2, micro, micro2, hyper, hyper2, powerup, ultra, ultra2, ultra2i, ultra3, 386, 486, pentium, pentium_pro, 603, 604. -xdepend Analyze loops for data dependencies. -xipo=n Performs optimizations across all object files in the link step: 0=off, 1=on, 2=performs whole-program detection and analysis -xlibmopt This chooses the math library that is optimized for speed. -xO1 Does basic local optimization (peephole). -xO2 xO1 and more local and global optimizations. -xO3 Besides what xO2 does, it optimizes references or definitions for external variables. Loop unrolling and software pipelining are also performed. -xO4 xO3 plus function inlining. -xO5 Besides what xO4 does, it enables speculative code motion. -xopenmp Enable explicit parallelization with C OpenMP directives. -xpad=common[:] Pad common block variables, for better use of cache. n specifies the amount of padding to apply. If no parameter is specified then the compiler selects one automatically. -xpad=local[:] Pad local variables only, for better use of cache. n specifies the amount of padding to apply. If no parameter is specified then the compiler selects one automatically. -xprefetch[=value] Enable prefetch instructions on those architectures that support prefetch, such as UltraSPARC II (-xarch=v8plus, v8plusa, v9plusb, v9, v9a, or v9b) auto Enable automatic generation of prefetch instructions no%auto Disable automatic generation of prefetch instructions explicit Enable explicit prefetch macros no%explicit Disable explicit prefetch macros yes -xprefetch=yes is the same as -xprefetch=auto,explicit no -xprefetch=no is the same as -xprefetch=no%auto,no%explicit Defaults If -xprefetch is not specified, -xprefetch=no%auto,explicit is assumed. If only -xprefetch is specified, -xprefetch=auto,explicit is assumed. -xprefetch_level Insert prefetches in loops with control flow -xprefetch_level=1 compiler inserts prefetches only in loops with no control flow -xprefetch_level=2 compiler inserts prefetches in loops with control flow -xprefetch_level=3 compiler aggressively inserts prefetches in loops with control flow -xprofile=collect Collect profile data for feedback directed optimizations. -xprofile=use Use data collected for profile feedback. -xrestrict[=f1,...,f2,%all, Treat pointer-valued function %none] parameters as restricted pointers. The default is %none. Specifying -xrestrict is equivalent to specifying -xrestrict=%all. -Xt Assume K & R conformance, allow ANSI C. -xtarget=native Same as -native -xvector Enable automatic calls to SPARC vector math library functions. ------------------------------------------------------------------ Kernel Parameters Flag Description shmsys:shminfo_shmmin Minimum size of system V shared memory segment that can be created. shmsys:shminfo_shmmax Maximum size of system V shared memory segment that can be created. This parameter is an upper limit that is checked before the system sees if it actually has the physical resources to create the requested memory segment. shmsys:shminfo_shmmni System wide limit on number of shared memory segments that can be created. shmsys:shminfo_shmseg Limit on the number of shared memory segments that any one process can create. tune_t_fsflushr Specifies the number of seconds between fsflush (system daemon for file system flushing) invocations. autoup Along with tune_t_flushr, autoup controls the amount of memory examined for dirty pages in each invocation and frequency of file system sync operations. ------------------------------------------------------------------ Environment Variables Flag Description OMP_DYNAMIC Enables or disables dynamic adjustment of the number of threads available for execution of parallel regions. OMP_NUM_THREADS Sets the number of threads to use during execution, unless that number is explicitly changed by calling the OMP_SET_NUM_THREADS subroutine. MT_BIND_PROCESSOR This environment variable can be used to bind the LWPs (lightweight processes) of a multithreaded program to processors. Performance can be enhanced with processor binding, but performance degradation will occur if multiple LWPs are bound to the same processor. MT_BIND_PROCESSOR = TRUE: bind LWPs to processors. MT_BIND_PROCESSOR = FALSE: do not bind LWPs to processors (default). For MT_BIND_PROCESSOR=TRUE, LWPs are bound in a round-robin fashion starting with processor whose "virtual-id" is 0. Virtual processor IDs are consecutive integers that start with 0, and may or may not be identical to the actual processsor IDs. If n processors are available online, then their virtual processor IDs are 0, 1, ..., n-1. STACKSIZE A default stacksise of 4 MB (for 32-bit programs) and 8 MB (for 64-bit programs) is used for additional threads created in an OpenMP program. The environment variable STACKSIZE can be used to set it to a different value. For example setenv STACKSIZE 2048 creates threads with stacksize of 2 MB each. -------------------------------------------------------- src.alt modification for 318.galgel_m peak runs The src.alt method was used in 318.galgel_m to use a modified version of the file eigQR.f90 for portability to LAPACK version 3.0. This change allows linking with Sun Performance Library, which implements optimized LAPACK version 3.0 routines. The change was simple a one-line addition that initializes the parameter LWORK prior to the DHSEQR call. diff src/eigQR.f90 src/src.alt/eigQR/eigQR.f90 < C a l l DHSEQR ('E', 'N', N, ILO, IHI, --- > Lwork = N > C a l l DHSEQR ('E', 'N', N, ILO, IHI, ---------------------------------------------------------- ptmalloc use for 330.art_m peak runs A publically available malloc implementation: ptmalloc library was linked in 330.art_m peak runs. ptmalloc is available as part of the GNU C library as well as a stand-alone package. The README file in the ptmalloc distribution contains following regarding its availability: "ptmalloc - a multi-thread malloc implementation =============================================== .... As part of the GNU C library, the source files are available under the GNU Library General Public License (see the comments in the files). But as part of this stand-alone package, the code is available under the (probably less restrictive) conditions described in the file `COPYRIGHT'. In any case, there is no warranty whatsoever for this package." The version used in 330.art_m peak runs was downloaded from (urls valid as of Dec 26, 2001) http://www.cs.colorado.edu/~zorn/Malloc.html or http://www.malloc.de/en/index.html The ptmalloc downloaded from above urls was compiled as (no source changes were made) cc -G -KPIC -O -DUSE_PTHREADS=1 -DUSE_TSD_DATA_HACK -D_REENTRANT \ -DTHREAD_STATS=1 -DMALLOC_HOOKS ptmalloc.c -o libptmalloc.so The libptmalloc.so was then linked in such that malloc/free calls in 330.art_m source for peak runs were resolved from this library (see the config file: 330.art_m options, for details).