Hi, I'm trying to make a threaded app with database connections. I was having low performance (20% cpu usage) because the site sending the data is limited in speed. So I tried launching another process of my program and I got to do twice as much,as expected. So I tried to make my app multithreaded. To feed the threads, I need to query a database (READ), and the threads themselves do database access too (Write). So I went with something like this: 
$dbh=...
$sth->execute()
$sth->bind_columns(...)

t1= new Thread \&processor;
t2= new Thread \&processor;

t1->join();
t2->join();
#ends here#
sub hitMe { # :locked? 
   $sth->fetch();
   return (columns...);
}

sub processor {
   my $dbconn....
   my $dbh...

   while(@data=hitme()) {
     process stuff;
     $dbh->something();
   }
}

[download]
But it complains that the connection is already being used by thread N (program's main thread) and that db handlers aren't shared. So how can I feed my threads with data from the db in a synchronized manner? Thanks

In reply to databases and multithreading by hjf

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