Troubleshooting locking problems in WebSphere Commerce with DB2
Introduction
The database is the most critical component of a WebSphere Commerce site, and because of its dynamic nature, it requires continuous attention. The WebSphere Commerce database can experience lock contention issues as a result of poor maintenance, un-tuned SQLs, or multiple threads going after the same data. As most of the shoppers' interactions rely on the database, these database issues directly impact a user's experience on the site, resulting in error pages and slow responsiveness.
This article introduces techniques to identify and troubleshoot typical locking problems in a WebSphere Commerce running with a DB2 database.
Understanding the problem
Why is it important to prevent and fix locking problems?
Locking problems can severely impact your WebSphere Commerce site. The database is involved in nearly every transaction that occurs on your WebSphere Commerce store, therefore it is a critical part of your environment.
If your WebSphere Commerce site is live in production, locking problems may affect the shopper's experience. For example, it can affect the shopper's ability to place orders, which leads to loss of sales. Locking problems can also affect the ability to perform regular store operational tasks, such as updating store catalog information, creating promotions, or processing backend requests. These problems cause loss of revenue and project delays, or can create additional costs to your IT department.
Therefore, it is critical to monitor your WebSphere Commerce database to ensure it is performing optimally and to reduce the probability of such problems from occurring. Furthermore, if problems do occur, it is important to quickly identify the root cause to minimize potential impact to your business.
This article is intended for WebSphere Commerce administrators who maintain the health of a WebSphere Commerce system. It is for people interested in learning how to properly maintain a WebSphere Commerce DB2 database, how to identify DB2 locking problems, and how to handle locking problems.
Recognizing locking issues
The key to identifying a locking problem is recognizing the symptoms. Typical symptoms include:
- Slow response times for shoppers.
- System appears to be hung and cannot process any requests.
- Sudden decrease in sales or total number of completed orders.
- Problems running backend administrative tasks.
- Problems running scheduler commands.
Keep in mind that your site can experience these symptoms for multiple causes. The following sections show how to identify whether the problems are the result of locking issues in the database.