Solved

CLOSE_WAIT Process left on Database Server after Java program runs.

Posted on 2008-10-28
8
541 Views
Last Modified: 2013-12-20
Even though I am closing my resultset, prepared statement, and database connection in the finally area of a try-catch, it is leaving a process on the database server that gets set to CLOSE_WAIT and then after about 3 hours goes to a LISTEN state and sits there until either the database is restarted or the PID killed. Why is this happening? What else do I need to do to tell the database server to get rid of that process? This is a problem because we only allow so many connections and after this program runs a 20 times, they are all taken up. This is a very simple Java program running on a Suse Linux server using JDBC against a Progress 10 database. Thanks for your help!
0
Comment
Question by:HKersten
  • 4
  • 4
8 Comments
 
LVL 12

Accepted Solution

by:
jazzIIIlove earned 500 total points
Comment Utility
Hi there;

Maybe the problem is in PreparedStatement...

PreparedStatement  the statement is cached and then the execution path is pre determined on the database server allowing it to be executed multiple times in an efficient manner...

But i am not sure...

Best regards...
0
 

Author Comment

by:HKersten
Comment Utility
Thanks jazzIIIlove, I'll try removing the prepared statements and post back the results!
0
 

Author Closing Comment

by:HKersten
Comment Utility
Thank you so much for your help! I wouldn't of guessed that it was the Prepared Statement cuasing this issue. You've saved me a bunch of time!
0
 

Author Comment

by:HKersten
Comment Utility
It was the Prepared Statements causing this issue. I switched them to Statement and now it works fine. Thanks!
0
6 Surprising Benefits of Threat Intelligence

All sorts of threat intelligence is available on the web. Intelligence you can learn from, and use to anticipate and prepare for future attacks.

 
LVL 12

Expert Comment

by:jazzIIIlove
Comment Utility
but beware of sql injections...
0
 

Author Comment

by:HKersten
Comment Utility
Sorry, I was mistaken, that did not fix the issue. I had some LISTEN processes still on the database server and apparently they were from the script running before so when I changed to statements and re-ran, it didn't create another process. If one is out there, it doesn't create another one. So it must have something to do with caching the process but I don't know why. Please let me know if you have any other suggestions.
0
 
LVL 12

Expert Comment

by:jazzIIIlove
Comment Utility
Hi there;

I am not sure that will work and it's a bad practice but well, let's assign the statements to null after closing them...
or

if you using linux:
a batch:
ps -Ao pid,command | grep java | grep eclipse
or:
kill -9 `pidof process_name`
replacing process_name by the name of process you want to kill
or:

a java code to kill process:
http://www.koders.com/java/fid4E9CF0CCE742471D5F25669CB19F951B2B0F454D.aspx

or:
http://www.experts-exchange.com/OS/Unix/Q_23703468.html

Best regards...
0
 
LVL 12

Expert Comment

by:jazzIIIlove
Comment Utility
You can take the points back i guess if you want...

I don't mind...since your question is not yet solved...By the way, you debug the code?
0

Featured Post

How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

Join & Write a Comment

CCModeler offers a way to enter basic information like entities, attributes and relationships and export them as yEd or erviz diagram. It also can import existing Access or SQL Server tables with relationships.
Read about achieving the basic levels of HRIS security in the workplace.
This tutorial explains how to use the VisualVM tool for the Java platform application. This video goes into detail on the Threads, Sampler, and Profiler tabs.
Viewers will learn how to properly install Eclipse with the necessary JDK, and will take a look at an introductory Java program. Download Eclipse installation zip file: Extract files from zip file: Download and install JDK 8: Open Eclipse and …

772 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

10 Experts available now in Live!

Get 1:1 Help Now