Re^9: Threaded Code Not Faster Than Non-Threaded -- Why?

I'd suggest trying the following modification:

my $thread_term   :shared = 0;
my $threads_init  :shared = 0;
my $file_read_sem : shared;                                           
+                   ### Add this

...

   WORKER: while ( !$thread_term && defined ( my $file = $work_queue->
+dequeue ) )
   {
     {                                                                
+                   ### Add this
         lock $file_read_sem;                                         
+                   ### Add this
         open my $fh, '<', $file or do { lock $d_counter; $d_counter++
+; next WORKER };

         my $data = <$fh>;

         close $fh;
      }                                                               
+                   ### Add this
[download]

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

Comment on Re^9: Threaded Code Not Faster Than Non-Threaded -- Why? Download Code

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Re^10: Threaded Code Not Faster Than Non-Threaded -- Why? by Tommy (Chaplain) on Jan 06, 2014 at 18:27 UTC
I'd suggest trying the following modification ...To prevent disk thrashing? Tommy A mistake can be valuable or costly, depending on how faithfully you pursue correction	[reply]
Re^11: Threaded Code Not Faster Than Non-Threaded -- Why? by BrowserUk (Patriarch) on Jan 06, 2014 at 19:57 UTC
To prevent disk thrashing? Yes. But you'll need to try it; and the effects will probably vary for different file systems. For lots of small files it might speed things up; for lots of big ones it might slow things down. For a mix; you'll need to measure. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply]