Solaris 8 & Perl 5.8.0 ithreads not using all the CPUs

Hi there,

 The code below is  executed on a Solaris 8 machine, with 4 CPUs
I would "expect" with values >4 for $MaxSem, that all the CPUs would be utilized
for the parsing. The parsing is quite CPU intensive, running ~20minutes for the 24files
on all four CPUs.

 However, according to top/vmstat/iostat/etc. the max usage for $MaxSem set to 5 or 4
is <70%, without any real disk activity not blocking for disk IO (it's a 4GB RAM machine, 
and the files are allready cached/buffered when it hit the foreach loop)

Thus I'm missing the utilization of more than 1CPU for this :(

Please advise

Hendrik
---code.pl----

use threads;
use Thread::Queue;
use Thread::Semaphore;

#The Semaphore that dictates the max concurrent threads...
my $MaxSem = Thread::Semaphore->new(5);
#The semaphore that keeps the output serialized
my $OutputLock = Thread::Semaphore->new(1);

        foreach $File (@FList){

          async {
            $MaxSem->down(1); #Locking to prevent too many threads simultaneously..
            %Output=&Parse($File);
            $MaxSem->up(1);
            $OutputLock->down(1);
              print {$OFile} $Output;
            $OutputLock->up(1);
          };
        } #FList

        #Make sure none is still running:
        foreach $thr (threads->list) { 
          print "Thread id: ".$thr->tid."\n"
            if $DEBUG >1;
          $thr->join; }
                    
-----code.pl------
# psrinfo -v
Status of processor 0 as of: 09/28/03 11:16:39
  Processor has been on-line since 09/26/03 10:44:08.
  The sparcv9 processor operates at 440 MHz,
        and has a sparcv9 floating point processor.
Status of processor 1 as of: 09/28/03 11:16:39
  Processor has been on-line since 09/26/03 10:44:09.
  The sparcv9 processor operates at 440 MHz,
        and has a sparcv9 floating point processor.
Status of processor 2 as of: 09/28/03 11:16:39
  Processor has been on-line since 09/26/03 10:44:09.
  The sparcv9 processor operates at 440 MHz,
        and has a sparcv9 floating point processor.
Status of processor 3 as of: 09/28/03 11:16:39
  Processor has been on-line since 09/26/03 10:44:09.
  The sparcv9 processor operates at 440 MHz,
        and has a sparcv9 floating point processor.
# uname -a
SunOS server 5.8 Generic_108528-13 sun4u sparc SUNW,Ultra-80

% perl -V
Summary of my perl5 (revision 5.0 version 8 subversion 0) configuration:
  Platform:
    osname=solaris, osvers=2.8, archname=sun4-solaris-thread-multi
    uname='sunos niv-svr-03 5.8 generic_108528-13 sun4u sparc sunw,ultra-80 '
    config_args='-D'
    hint=previous, useposix=true, d_sigaction=define
    usethreads=define use5005threads=undef useithreads=define usemultiplicity=define
    useperlio=define d_sfio=undef uselargefiles=define usesocks=undef
    use64bitint=undef use64bitall=undef uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='gcc', ccflags ='-D_REENTRANT -fno-strict-aliasing -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
    optimize='-O',
    cppflags='-D_REENTRANT -fno-strict-aliasing -I/usr/local/include -D_REENTRANT -fno-strict-aliasing -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64'
    ccversion='', gccversion='2.95.3 20010315 (release)', gccosandvers='solaris2.8'
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=4321
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
    alignbytes=8, prototype=define

  Linker and Libraries:
    ld='gcc', ldflags =' -L/usr/local/lib '
    libpth=/usr/local/lib /usr/lib /usr/ccs/lib
    libs=-lsocket -lnsl -ldl -lm -lrt -lpthread -lc
    perllibs=-lsocket -lnsl -ldl -lm -lrt -lpthread -lc
    libc=/lib/libc.so, so=so, useshrplib=true, libperl=libperl.so
    gnulibc_version=''
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags=' -Wl,-E -R /usr/local/lib/5.8.0/sun4-solaris-thread-multi/CORE'
    cccdlflags='-fPIC', lddlflags=' -Wl,-E -G -L/usr/local/lib'


Characteristics of this binary (from libperl): 
  Compile-time options: MULTIPLICITY USE_ITHREADS USE_LARGE_FILES PERL_IMPLICIT_CONTEXT
  Built under solaris
  Compiled at Aug  4 2003 22:33:45
  @INC:
    /usr/local/lib/5.8.0/sun4-solaris-thread-multi
    /usr/local/lib/5.8.0
    /usr/local/lib/site_perl/5.8.0/sun4-solaris-thread-multi
    /usr/local/lib/site_perl/5.8.0
    /usr/local/lib/site_perl
    .
%

Running at "peak" load:
CPU minf mjf xcal  intr ithr  csw icsw migr smtx  srw syscl  usr sys  wt idl
  0    0   0  810   871  300 5754  545  202 3949    0  8780   75  15   0  10
  1    0   0  527   568  101 6082  538  240 3905    0  8849   72  12   0  16
  2    0   0  485   594  127 5997  523  224 3903    0  8969   72  13   0  15
  3    0   0  460   675  100 6053  664  202 3939    0  8854   71  11   0  18
CPU minf mjf xcal  intr ithr  csw icsw migr smtx  srw syscl  usr sys  wt idl
  0    0   0  754   901  300 5282  568  182 3271    0  7620   70  12   0  18
  1    0   0  450   528  101 5394  479  199 3531    0  8109   67  12   0  20
  2    0   0  462   517  100 5281  477  194 3644    0  8494   75  12   0  12
  3    0   0  436   556  100 5530  511  180 3512    0  8339   76  10   0  14
CPU minf mjf xcal  intr ithr  csw icsw migr smtx  srw syscl  usr sys  wt idl
  0    0   0  718   868  300 5572  548  196 3521    0  8265   76  13   0  11
  1    0   0  443   467  104 5141  412  178 3637    0  8036   78  11   0  11
  2    0   0  414   501  102 5104  446  189 3442    0  7738   66  13   0  21
  3    2   0  411   527  100 5239  486  178 3442    0  8002   73  12   0  15