I'm getting the feeling that we may have problems in more than one area. I am new to
most of this, so I am learning as I go.
I can give you an example of when Apache will stay connected. If I connect to the
database and, before the disconnect, I have a
call to a subroutine that does not exist, then the script will blow up. So, it never
gets to the disconnect statement resulting in
the Apache process staying attached to the server. In a case like this, it may just
have been a typo, but the programmer that wrote
the script probably is not authorized to stop the Apache processes. The more I think
about it, I may end up having to contact
Oracle to find out if there is a way to keep any single process from being connected
to the database over a specified amount of
time.
Below is a part of a script that if ConvertNumToDate() is not in the package
UTILITIES, then the script would never detach from the
database.
my $dbh = DBI->connect("dbi:RDB:ATTACH FILENAME meltdbdir:melt_rdb")
or die "Can't connect to Melt Shop database: $DBI::errstr\n";
my $statement = "SELECT heat_number, tap_grade, met_final_ht_grade, bof_tap_date_time,
blow_time
FROM master_heats
WHERE heat_number = $heatToGet ";
my $sth = $dbh->prepare($statement);
#Run it.
$sth->execute();
while( @data = $sth->fetchrow_array()) {
..........
if( $data[3] ne "" ) {
$totalDate1 = UTILITIES::ConvertNumToDate($data[3]);
........
}
Thank you so much for your help,
Jen Landberg
"Craig A. Berry" <[EMAIL PROTECTED]> on 03/21/2003 03:38:59 PM
To: Jennifer Landberg/[EMAIL PROTECTED]
cc: [EMAIL PROTECTED]
Subject: Re: DBD::RDB locking RDB databases
Jen,
I don't have an answer but I do have a few suggestions.
At 11:22 AM -0500 3/21/03, [EMAIL PROTECTED] wrote:
>We're running:
>OpenVMS 7.2-1
>Compaq Secure Web Server (CSWS) 1.2 (based on Apache 1.3.20)
>Perl 5.6.1 (gotten from Compaq's site)
>CSWS Perl V1.1 (based on mod_perl 1.25)
Note that all of those things are supported by HP,
>DBI 1.201
>DBD::RDB 1_15
whereas whatever support there is for these will be here and/or on
the dbi-users list,
>RDB V7.0-31
and of course this is supported by Oracle. Determining which
component is really having the problem might be your first step in
getting a resolution.
>We are using the RDB module in Perl to access an RDB database on the
>same machine. The problem that I'm having is that if there is an
>error in the script after the connect statement, then Apache will
>stay connected to the database indefinately.
Without more detail it's impossible to say with certainty where the
problem is. I would start by examining the script for proper error
handling. Ideally the script should detect errors and (depending on
the script's design) possibly disconnect from the database rather
than simply blowing up, exiting early, or looping to get the next
request. Perhaps it disconnects at the end of a successful run but
possibly (just a guess) neglects to disconnect when it encounters an
error? Do you have a 10-20 line reproducer that illustrates the
problem? What exactly do you mean by "an error in the script"?
>If Apache is not restarted to get it to detach from the database,
>then it will eventually lock up RDB to the point that no one will be
>able to access any of the databases. What can I do to keep this
>from happening?
There may be some less drastic managerial mechanisms for getting
unhung when this is going on. I'm quite rusty on Rdb and never
really dealt with it from the DBA perspective, but there's got to be
a way for the DBA to view what connections are active and disconnect
one that is causing trouble. For Apache, it's probably possible to
shut down one of the APACHE$xxxxx processes without restarting the
whole server, but check your docs and/or other support channels on
that.
Don't neglect standard analytical tools to examine the state and
resource consumption of the database connection and associated web
server process. Depending on the origin of the problem these may
give insight into it, or they may be red herrings and only show the
consequences of the problem and not the problem itself.
--
________________________________________
Craig A. Berry
mailto:[EMAIL PROTECTED]
"... getting out of a sonnet is much more
difficult than getting in."
Brad Leithauser
