multithreading - Perl Tcp 传输不一致

Question

这是我在 Perl 中使用 TCP 传输文件的以下代码。我们正在使用线程将“n”个文件传输到其他服务器，并且我们在发送之前将每个文件分块为 5mb。对于以下函数中的大多数文件，我遇到的问题是“连接断开”或“数据包标头”接收 0 个字节。不知道线程 tcp transfer 的原因和学习阶段是什么。所以请建议我需要如何调试，无论是代码中的问题还是我们正在传输的服务器中的问题，我需要应用什么解决方案。

    #GET THE PACKET HEADER
    my $data;
    my $tempdata;
    my $datalen = 0;
    my $templen = 0;
    my $retrycount = $self->{retrycount};

    my $mark = time();
    my $iloops = 0;
    my $waitlist = IO::Select->new($self->{sock});
    while($datalen < 9)
    {
            my $iloops++;
            usleep( $usleep_wait );

            if($waitlist->can_read($timeout || 0)) { $templen = $self->{sock}->sysread($tempdata, 9 - $datalen); } else { $templen = 0; $! = EWOULDBLOCK; }
            if(($templen || 0) > 0)
            {       
                    #EVERYTHING'S FINE
                    print_message(LOGLEVEL_TRACE, "Got $templen bytes", LOG_TAG) unless ( $templen == 9 ); # 
                    $mark = time();                 #RESET THE TIMEOUT
                    $data .= $tempdata;
                    $datalen += $templen;
                    
                    last if $datalen == 9;
                    next;
            }
            #AN IRRECOVERABLE ERROR HAPPENED (i.e. WE CAN'T JUST WAIT IT OUT)
            elsif(!defined $templen)
            {       
                    if($! != EWOULDBLOCK && $! != EAGAIN && $! != EINTR && $! != EINPROGRESS)
                    {       
                            my $err = $!;
                            
                            #DISCONNECTION
                            print_message(LOGLEVEL_ERROR, "__grab_data: Connection was dropped ($@, $!).", LOG_TAG); # if !defined $self->__reconnect();
                            $self->{sock}->close();
                            #print_message(LOGLEVEL_INFO, "Connection was dropped, but was re-established ($err)", LOG_TAG);
                            return undef;
                    }
                    else
                    {       
                            print_message(LOGLEVEL_ERROR, "__grab_data: An unknown error happened ($@, $!).", LOG_TAG);
                            $self->{sock}->close();
            elsif($templen == 0)
            {
                    print_message(LOGLEVEL_TRACE, "Finished the stream, nothing to collect", LOG_TAG);
                    last;
            }
            ## OPTIONAL TIMEOUT FOR NONBLOCKING REQUESTS
            elsif(defined $timeout)
            {
                    return undef if time() - $mark > $timeout;
            }

            usleep( $usleep_wait );
            print_message(LOGLEVEL_FAILURE, "Connection dropped whilst trying to receive data", LOG_TAG) if !$self->is_connected();
    }
    my $interim = time();


    #WE DIDN'T RECEIVE THE WHOLE HEADER
    if($datalen != 9)
    {
            usleep( $usleep_whole_header_wait );
            print_message(LOGLEVEL_ERROR, "Packet header is truncated (we only got $datalen bytes, '$data')", LOG_TAG);
            return undef;
    }

标签： multithreadingperltcplistenerpacket-loss