Multithreading Perl线程有时会卡住（其中一些线程正在等待futex）

我正试图运行的多线程Perl应用程序（在Redhat7.4上使用Perl5.10.1）遇到了一个问题。该问题已通过以下设置重现（设置类似于原始Perl应用程序）：

有两个文件：main.pl、module1.pm

main.pl：

• 完成一组任务的顶级脚本，作为“main.pl”调用

我无法理解为什么会发生这种情况（可能与线程：：队列或管道等有关），如果有人能帮我解决这个问题，那就太好了。我最终希望能够运行所有测试，而不出现任何futex等待/挂起问题。我试过：

• 使用IPC:：Run的超时选项检查控件是否返回，但此处没有运气
• 使用open3（）代替IPC:：Run:-问题仍然存在，并且比IPC:：Run更频繁

注:

• 当我使用Perl5.16.3时，这个问题不会出现。但是我需要使用Perl 5.10.1使原始应用程序正常工作，因此如果有人能帮助我理解如何解决这个问题，那将是非常棒的：）
• 在module1:：dummy（）中，如果将$loCmd更改为“sleep”，将$loArgs更改为（比如）“10”，则问题不会出现（给人的印象是它可能与管道/IO缓冲区有关）
• 被卡住的线程数可能因不同的运行而有所不同，有时所有线程都会在没有任何问题的情况下完成（可能存在争用条件）

---

如果使用最新的perl版本5.32运行，是否会遇到相同的问题？

运行['bsub'、'-q regresse'、'-R ws70'、'-K'、“$loCmd$loArgs”]

此命令的作用是什么？其他命令也有同样的问题吗？例如，尝试替换一个伪命令，如

sleep

实际上，我们需要一些有意义的替换来替换

bsub

命令，或者一个指向如何安装它的指针，否则代码在测试设置中不容易使用。我必须使用bsub命令在远程LSF计算设施上运行lsfScript.pl脚本。我将编辑脚本以删除此命令，并在本地计算机上运行一个更简单的命令。我已删除

bsub

命令，并将其更改为一个简单的

echo

命令。

# main.pl
#!/apps/perl/5.10.1/bin/perl

use strict;
use warnings;
use v5.10.1;
use threads;
use threads::shared;

use module1;

use lib "<path to Thread::Queue module>"; 
use Thread::Queue;

my $glNumTests = shift();       # Number of tests(jobs) to run
my $glMaxThreads = shift();     # What is the max allowed number of workers (threads) for queue mode

my $q = Thread::Queue->new();    # A new empty queue

# Worker thread
sub worker
{
    # Thread will loop until no more work
    while (defined(my $item = $q->dequeue())) {
        # Do work on $item
        sleep(5); # dummy pre-work
        $item->dummy(); # Actual task that needs to be run by each thread
    }
}

sub start_threads
{
    my $loNumThreads = shift();
    $loNumThreads = $loNumThreads > $glMaxThreads ? $glMaxThreads : $loNumThreads;
    print "Creating $loNumThreads threads...";
    for ( 1..$loNumThreads )
    {
        threads->create(\&worker);
    }
    print "done\n";
}

sub initialize
{
    my @lotests;
    my $loNumTests = shift();
    for my $i (1..$loNumTests)
    {
        push(@lotests,"Test_".$i);
    }
    return \@lotests;
}

sub launchjobs
{
    my @lotests = @{shift()};
    my $tests = {};
    
    # Create objects
    foreach my $lotest (@lotests)
    {
        $tests->{$lotest}->{"obj"} = module1->new($lotest);
    }
    
    # Start the threads before adding work to the queue
    start_threads(scalar(@lotests));
    
    # Adding work to queue
    foreach my $lotest (@lotests)
    {
        $q->enqueue($tests->{$lotest}->{"obj"});
    }
    # No more work to be added
    $q->end();

    # Wait for threads to finish
    foreach my $thr ( threads -> list() )
    {
        $thr->join();
    }   
}

launchjobs(initialize($glNumTests));

# module1.pm
package module1;

use lib "<InstallationPath>/IPC-Run-20200505.0/lib";
use IPC::Run qw( run ); 

sub new
{
    my $class = shift();
    my $test = shift();
    my $self = {};
    $self->{"testName"} = $test;
    system("\\mkdir -p test_output/$self->{testName}");
    # Create new file track.log for this object
    open(my $OFH,">","test_output/$self->{testName}/track.log") || die "Cannot open track.log for writing in new\n";
    close($OFH);
    bless($self,$class);
    return $self;
}

sub logTracker
{
    # Writes out the message to track.log file 
    my $self = shift();
    my $message = shift();  
    open(my $OFH,">>","test_output/$self->{testName}/track.log") || die"Cannot open track.log for writing\n";
    print $OFH $message;
    close($OFH);    
}

sub dummy
{
    my $self = shift();
    print "running $self->{testName}\n";

    my $loCmd = "echo"; # Command to be run
    my $loArgs = "This is test $self->{testName}"; # Arguments to the above command
    
    $self->logTracker("Calling run\n");
    run [$loCmd,$loArgs],'>&',"test_output/$self->{testName}/output";
    $self->logTracker("run completed\n");
}
1;

strace: Process 41187 attached with 8 threads
[pid 42343] read(22,  <unfinished ...>
[pid 42292] read(20,  <unfinished ...>
[pid 42291] read(25,  <unfinished ...>
[pid 42282] read(24,  <unfinished ...>
[pid 42234] read(43,  <unfinished ...>
[pid 42212] read(18,  <unfinished ...>
[pid 41187] futex(0x7ff2597939d0, FUTEX_WAIT, 42212, NULL <unfinished ...>
[pid 42338] read(16,

-perl,41187 main.pl 1000 128
    |-perl,42614 main.pl 1000 128
    |-perl,42615 main.pl 1000 128
    |-perl,42616 main.pl 1000 128
    |-perl,42617 main.pl 1000 128
    |-perl,42618 main.pl 1000 128
    |-perl,42620 main.pl 1000 128
    |-perl,42621 main.pl 1000 128
    |-{perl},42212
    |-{perl},42234
    |-{perl},42282
    |-{perl},42291
    |-{perl},42292
    |-{perl},42338
    `-{perl},42343