Re: Running PERL SCRIPTS in Parallel

Net::OpenSSH::Parallel does not support parallelization inside the host (it's on the TODO list). Though, for simple cases it can be done using the parsub action:

# untested!

require POSIX;

sub ssh_run_parallel {
   my ($label, $ssh, @cmds) = @_;
   my @pids = map $ssh->spawn(@$_), @cmds;
   my $error = 0;
   for (@pids) {
     waitpid $_, 0;
     $error ||= $?;
   }
   POSIX::_exit($error);
}

my $pssh = Net::OpenSSH::Parallel->new();
$pssh->add_host($_) for @hosts;
$pssh->push('*', scp_put => '/root/cpu.pl', '/root/memory.pl', '/root/
+');
$pssh->push('*', parsub => \&ssh_run_parallel,
            ['/usr/bin/perl', '/root/cpu.pl', '/tmp/cpu'],
            ['/usr/bin/perl', '/root/memory.pl', '/tmp/memory']);

$pssh->run;
[download]

update: the error pointed by rahulruns below has been fixed!

Comment on Re: Running PERL SCRIPTS in Parallel Select or Download Code

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Re^2: Running PERL SCRIPTS in Parallel by rahulruns (Scribe) on May 22, 2013 at 08:15 UTC
I tried to run the code but was not able to understand my @pids = map $ssh->spawn(@$_) for @cmds; It is giving error Not enough arguments for map at stress.pl line 44, near ") for " Execution of stress.pl aborted due to compilation errors. I am not able to troubleshoot. Could anyone help `my @pids = map $ssh->spawn(@$_) for @cmds; Error Not enough arguments for map at stress.pl line 44, near ") for " Execution of stress.pl aborted due to compilation errors.` [download]	[reply] [d/l]
Re^3: Running PERL SCRIPTS in Parallel by salva (Canon) on May 22, 2013 at 08:23 UTC
I have corrected the code. `my @pids = map $ssh->spawn(@$_), @cmds;` [download] is equivalent to ... `my @pids; for my $cmd (@cmds) { push @pids, $ssh->spawn(@$cmd); }` [download] It uses the Net::OpenSSH object passed to the sub to start all the commands in parallel.	[reply] [d/l] [select]
Re^3: Running PERL SCRIPTS in Parallel by rahulruns (Scribe) on May 22, 2013 at 08:22 UTC
Thank You for the Fix. I too was able to troubleshoot `my @pids = map $ssh->spawn(@$_) @cmds;` [download]	[reply] [d/l]