>>>>> "SWM" == Steven W McDougall <[EMAIL PROTECTED]> writes:
>> Single thingee access mediation, should be done automatically by perl.
>> The multi-thingee complex mediation should have the user step in, since
>> solving it (correctly and efficiently) is a complex problem.
SWM> I'm not sure we have a common understanding of the terms we are using.
SWM> Can you give some examples showing what happens
SWM> - with single thingee access mediation
my $a :shared;
Perl handles the mutex.
SWM> - without single thingee access mediation
my $a;
Perl simply ignores locking. Thread gets the value of the winner
in a race condition. Perl does _not_ crash and burn. Internal
structures, mallocs, and accesses are properly mutexed.
SWM> - with multi-thingee complex mediation
my $pumpkin;
my @foo :shared_nolock; # Just made this up.
my $foo_counter :shared_nolock; # Its spelled wrong
sub foo {
lock($pumpkin); # I'm a critical section
push(@foo, $bar);
$foo_counter++ unless $bar % 7
}
SWM> - without multi-thingee complex mediation
my @foo :shared;
my $foo_counter :shared;
push(@foo, $bar);
$foo_counter++ unless $bar % 7
There is nothing to keep $foo_counter and @foo in sync. Two
different unrelated items, that are each individually properly
syncronized by perl, but the whole is wrong.
<chaim>
--
Chaim Frenkel Nonlinear Knowledge, Inc.
[EMAIL PROTECTED] +1-718-236-0183
