Data collectors help you determine whether data that a transaction passed into an application is causing problems. When you configure data collectors AppDynamics accesses information in application code arguments, return values, and variables, as well as HTTP request data such as headers and cookies, and displays the information in Call Drill Down panels.
Collecting Diagnostic Data from Application Payload
Some application performance problems are related to the data processed in a request.
For example, consider a transaction that searches for a specific category. If a particular category has a problem, it can be difficult to diagnose the problem. You would need to:
- Isolate the name of the category that experienced a slow or failed search.
- Identify all the categories that experienced slow or failed searches.
- Identify other details, such as which users experienced problems accessing the search functionality.
AppDynamics can collect contextual business data either to correlate between different performance problems or to correlate a particular performance problem with the business data. The contextual data can be collected either from the HTTP payload data or from the methods that are invoked as part of the transaction.
AppDynamics can capture the following diagnostic data about the business context attached to the business transaction:
- The basic details such as the type of business transaction, URI, and the time stamp
- The HTTP parameters, cookies, session keys, and headers for the transaction
- User data gathered from any POJO or POCO method executed during the transaction
AppDynamics provides data collectors to collect the business context for each incoming business transaction. These data collectors capture the diagnostic data from all transactions that are slow, very slow, stalled or that experience any error during execution.
There are two types of data collectors:
- HTTP request data collectors for HTTP payload
- Method invocation data collectors capture parameters or the return value for a particular method
If data collectors are configured, the data appears in various panels, such as the HTTP Params, Cookies, and User Data sections, of a transaction snapshot. To access these panels see To view call graphs.
You can configure data collectors for a particular business transaction or for all business transactions in a business application.
Data collectors are different than information points, which gather data outside the context of a business transaction. See Data Collectors Versus Information Points.
To view the data collectors for a particular business transaction
1. In the business transactions list, select a business transaction.
2. Click the More Actions drop-down menu.
3. Click Configure Data Collectors to view the data collectors configured for that transaction.
To apply a data collector to a business transaction
1. Follow the instructions above in To View the Data Collectors for a Particular Business Transaction.
2. Move the data collector from the Available Data Collectors list to the Data Collectors list.
3. Click Save.