Your understanding is correct. It’s what I am looking for. However, due to the 
apache forking child nature, I don’t feel comfortable using SIGALARM.

We use Apache::DBI. I would prefer having enhancement in this module. Currently 
the module is implementing apache process wide global cache for db connections, 
which we already use. But one missing piece in this module is to handle the TTL 
(time-to-live) for a cached db connection.  If TTL were implemented, the module 
would have to disconnect from db connection after a pre-defined timeout so the 
oracle server process could be shut down more gracefully. Would it be possible 
to implement that? Or is it too hard to implement?

- xinhuan

From: Paul Silevitch <p...@silevitch.com<mailto:p...@silevitch.com>>
Date: Wednesday, November 12, 2014 at 11:53 PM
To: Xinhuan Zheng <xzh...@christianbook.com<mailto:xzh...@christianbook.com>>, 
modperl <modperl@perl.apache.org<mailto:modperl@perl.apache.org>>
Subject: Re: Disconnect database connection after idle timeout

I don't fully understand your need here.  I'm going to give my best.

You could set an alarm in the cleanup handler that calls the disconnect after a 
specified amount of time.  If a new request comes in, you could cancel the 
alarm in a postreadrequest handler (or something early in the cycle).  To cover 
the race condition where the disconnect happens right before the cancel, you 
could check to make sure the database connection is active right after the 
cancel is called.

HTH,

Paul

On Wed, Nov 12, 2014 at 9:36 PM, Xinhuan Zheng 
<xzh...@christianbook.com<mailto:xzh...@christianbook.com>> wrote:
Hello,

I am having a database connection management question. Our apache+mod_perl 
application initiates a database connection request when it needs to then do 
data processing. Afterwards, if there is no more requests coming to this apache 
process, the database connection basically will be sitting there in idle state 
for quite a while until the OS TCP/IP idle timeout has reached. At that point 
the database would send a message into its alert log, telling that a connection 
timeout has occurred and the server process will be cleaned. I would like to 
figure out if mod_perl application can implement keep-alive timeout mechanism. 
The mod_perl would maintain the database connection after it finishes some 
processing until an idle timeout defined in the application has reached, for 
example, 5 minutes. Then the mod_perl would initiate a database disconnection 
request so the server process can be cleaned more gracefully. We are using 
Oracle 11g database. I knew in 11G oracle has implemented the connection 
pooling. I would think the oracle side connection pooling would be the server 
side maintaining the connection idle timeout. Would it be possible on the 
client side the mod_perl implement something like that? I just don’t know which 
side is more appropriate and how on the client side it can implement something 
like that.

Thanks,
- xinhuan

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