RE: iThreads troubles

This cold medicine is throwing me for a loop.  What I meant to say was
"or at least it makes no mention of the use of arrays or hashes".





-----Original Message-----
From: Daniel Rychlik [mailto:[email protected]] 
Sent: Wednesday, April 19, 2006 9:59 AM
To: Mike Pomraning
Cc: [email protected]; [email protected]
Subject: RE: iThreads troubles

Thank you for the suggestions.  I will do so moving forward.

Reading through the Thread::Queue documentation it appears that it only
works with scalars and not arrays or hashes or at least makes no mention
of the use of arrays or scalars.  

I would like to use Thread::Queue if that's what it takes.  

This program is a beast....


-----Original Message-----
From: Mike Pomraning [mailto:[email protected]] 
Sent: Wednesday, April 19, 2006 9:27 AM
To: Daniel Rychlik
Cc: [email protected]; [email protected]
Subject: RE: iThreads troubles

On Wed, 19 Apr 2006, Daniel Rychlik wrote:

> Some of you have asked for code examples.
> 
> One of issues that I am having is when the thread enters into
> getAvailableResource routine its not seeing that the
> $Resources{'WAN1'}->{INUSE} = 1; has been made unavailable.  The idea
is
> for the next thread to pick up the next unavailable resource.  I tried
> to sleep(1) between thread creation, and also used threads::shared
> share(%Resources); which also failed.  

Dan,

A few quick remarks/suggestions.

First, please post the smallest possible code that reproduces your
symptoms:
pare down your problematic program, stuff it with stubs until you've got
a
cogent proof-of-problem.

Second, &share()ing your hash clears it [0], so populate it /after/ you
mark
it shared.  Additionally, the hash members themselves have to be
explicitly
shared, IIUC. [1]

Third, your 'INUSE' check looks to have a race.  You'll need to &lock(),
use
a semaphore, etc.  As others have suggested, Thread::Queue makes these
kinds
of problems a lot easier.  You could, perhaps, manage the "wan" and
"modem"
resources themselves in a queue -- pop off the next available one, use
it,
then re-queue it for another job later on.  TMTOWTDI.

[0] "When share is used on arrays, hashes, array refs or hash refs, any
    data they contain will be lost."
 
http://search.cpan.org/~jdhedden/threads-shared-1.01/shared.pm#BUGS_AND_
LIMITATIONS

[1] "This places restrictions on what may be assigned to shared array
and
    hash elements: only simple values or references to shared variables
are
    allowed..."
 
http://www.perldoc.com/perl5.8.4/pod/perlthrtut.html#Shared-And-Unshared
-Data

Good luck,
Mike
--
cat: .signature: Message too long