I don't quite know where to begin with this one.

I have a daemon process which has been dying unexpectedly and without any kind of warning. I think I've narrowed it down to an untie which doesn't return (or at the very least takes an abnormally long time to return).

Here are the open and close functions: 
sub _open_db { my $self = shift;
warn "_open_db $self $self->{NAME}\n";
    
    # sorted index
    $DB_BTREE->{'flags'} = 0;
    $DB_BTREE->{'compare'} = sub {
        my ($key1, $key2) = @_;
        $key1 <=> $key2;
    };
    if (tie(my %ip_db, 
            'DB_File', 
            $self->{IP_FILE}, 
            O_RDWR|O_CREAT, 
            0644, 
            $DB_BTREE)) {
        # Enable duplicate keys as well
        $DB_BTREE->{'flags'} = R_DUP;
        if (my $stamp_tie = 
            tie(my %stamp_db, 
                'DB_File', 
                $self->{STAMP_FILE}, 
                O_RDWR|O_CREAT, 
                0644, 
                $DB_BTREE)) {
            $self->{IP_DB} = \%ip_db;
            $self->{STAMP_DB} = \%stamp_db;
            $self->{STAMP_TIE} = $stamp_tie;
warn "_open_db OK IP_DB: $self->{IP_DB}" .
    "  STAMP_DB: $self->{STAMP_DB}  STAMP_TIE: $self->{STAMP_TIE}\n";
            return $self;
        }
        else { 
            $Err_Msg = "Can't open stamp db $self->{STAMP_FILE}: $!"; 
        }
warn "_open_db failed $Err_Msg\n";
        untie %ip_db;
warn "_open_db untie complete\n";
    }
    else { $Err_Msg = "Can't open IP db $self->{IP_FILE}: $!" }
warn "_open_db failed $Err_Msg\n";
    return 0;
}

sub close_db { my $self = shift;
warn "close_db $self\n";
    
    delete $self->{STAMP_TIE};
warn "delete STAMP_TIE complete\n";
    untie %{$self->{STAMP_DB}};
warn "untie STAMP_DB complete\n";
    delete $self->{STAMP_DB};
warn "delete STAMP_DB complete\n";
    untie %{$self->{IP_DB}};
warn "untie IP_DB complete\n";
    delete $self->{IP_DB};
warn "delete IP_DB complete\n";
    return 1;
}

[download]
The databases are opened: 
_open_db Db_file=HASH(0x838ad20) blacklist
_open_db OK IP_DB: HASH(0x83f4960)  STAMP_DB: HASH(0x83f429c)  STAMP_T
+IE: DB_File=SCALAR(0x83670f4)
_open_db Db_file=HASH(0x83670e8) notify
_open_db OK IP_DB: HASH(0x8367040)  STAMP_DB: HASH(0x83658b8)  STAMP_T
+IE: DB_File=SCALAR(0x841651c)
_open_db Db_file=HASH(0x83b4e84) notify_events
_open_db OK IP_DB: HASH(0x838adbc)  STAMP_DB: HASH(0x83b4e90)  STAMP_T
+IE: DB_File=SCALAR(0x841663c)
_open_db Db_file=HASH(0x842e370) tracking
_open_db OK IP_DB: HASH(0x84165dc)  STAMP_DB: HASH(0x84165d0)  STAMP_T
+IE: DB_File=SCALAR(0x842f914)
_open_db Db_file=HASH(0x80f53f0) tracking
_open_db OK IP_DB: HASH(0x842f8b4)  STAMP_DB: HASH(0x842e43c)  STAMP_T
+IE: DB_File=SCALAR(0x80f5540)

[download]
Then some time later, the databases are closed: 
close_db Db_file=HASH(0x842e370)
delete STAMP_TIE complete
untie STAMP_DB complete
delete STAMP_DB complete
untie IP_DB complete
delete IP_DB complete
close_db Db_file=HASH(0x80f53f0)
delete STAMP_TIE complete

[download]
One database is closed, but then the second database never returns from the first untie. The close/open cycle can repeat sucessfully for days on end, or it can zone out on the first try. Sometimes it stops on the first untie, sometimes the second. I haven't been able to reliably reproduce the error, but I've noticed I can 'encourage it' by causing more activity against the databases. The databases aren't unusually large, maybe 200k for the largest, most are less than 50k. I'm at a loss.

In reply to Problem with untie by ruzam

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