Informatica Tracing Levels: Which One to Use and When

Informatica PowerCenter has four tracing levels: Terse, Normal, Verbose Initialization, and Verbose Data, which control how much detail the Integration Service writes to the session log. Normal is the default for every transformation. You can set a tracing level on individual transformations or override it for the whole session. Use Normal in production, Terse when you want minimal logging, and the Verbose levels only while debugging, because Verbose Data logs every row, adds overhead, and can write sensitive values into log files.

Tracing levels are among the simplest settings in PowerCenter and among the easiest to get wrong. Too little detail makes a failed session hard to diagnose; too much slows sessions and fills logs with data nobody should store. This article explains each level, where it is configured, and how to choose.

Quick Summary: Tracing levels set the amount of detail in the session log, from Terse (minimal) to Verbose Data (every row). The default, Normal, is enough to diagnose most failures. Raise a single transformation to a verbose level only while debugging, then set it back. Treat Verbose Data logs as sensitive, since they contain actual row values.

Key Takeaways

There are four tracing levels. Terse, Normal, Verbose Initialization, and Verbose Data.
Normal is the default for every transformation and is enough for most production troubleshooting.
Session settings can override transformation settings. The session-level "None" option means the mapping's own tracing levels apply.
Verbose Data logs every row. Use it briefly, on small data, while debugging.
Logs can hold sensitive data. Verbose Data writes row values to the session log, so protect and purge those logs.
Terse gives a slight performance boost by writing the minimum to the log.

What Are Informatica Tracing Levels?

A tracing level controls how much information the Integration Service writes to the session log while a workflow runs. In a mapping, each transformation has its own tracing level, so you can ask for more detail from one problem transformation without flooding the log from every other one. The session log then becomes the main record for diagnosing failures and understanding run behavior, which makes tracing a practical part of day-to-day Informatica ETL operations.

The Four Tracing Levels

Level	What the Integration Service Logs	Typical Use	Overhead
Terse	Initialization information, error messages, and notification of rejected data	Stable jobs where minimal logging is enough	Lowest
Normal (default)	Initialization and status information, errors encountered, and skipped rows due to transformation row errors; summarizes session results, not individual rows	Production runs and most troubleshooting	Low
Verbose Initialization	Everything in Normal, plus additional initialization details, names of index and data files used, and detailed transformation statistics	Tuning transformations, such as reviewing cache behavior	Moderate
Verbose Data	Everything in Verbose Initialization, plus each row that passes into the mapping, with row data for all rows in a block	Debugging a transformation that is not behaving as expected	Highest

A note on "None": at the session level you will also see a None option. It is not a fifth logging level. It means the session does not override anything, so the tracing levels set in the mapping apply.

Where to Set Tracing Levels

At the transformation level. Each transformation has a Tracing Level property, which defaults to Normal. This lets you target one transformation.
At the session level. In the session's Config Object tab, the Override Tracing option applies a single tracing level to all transformations in the session, replacing the per-transformation settings.

By default, the Integration Service uses the tracing levels configured in the mapping. Because a session override replaces them, it is easy to forget an override that was set during debugging, which is a common reason a production session logs far more than expected. For where sessions, mappings, and repositories fit together, see our PowerCenter architecture overview and our article on developing global and local repositories in Informatica.

Which Level to Use

Situation	Suggested Level
Stable production session with good monitoring elsewhere	Terse or Normal
General production default	Normal
A transformation is producing wrong or missing results	Verbose Data on that transformation only, on a small test data set
Reviewing cache sizes or transformation statistics while tuning	Verbose Initialization
Reproducing a defect in a development environment	Verbose Data, temporarily

Informatica's own guidance is to change to a Verbose setting only when you need to debug a transformation that is not behaving as expected, and to use Terse for a slight performance boost when minimal logging is acceptable.

Verbose Data: Handle with Care

Verbose Data is powerful and easy to misuse, for three reasons:

Performance. Writing every row to the log adds overhead, and on large data volumes it can slow a session noticeably.
Log size. Row-level logging can produce very large files that consume disk space and are hard to read.
Data exposure. Because Verbose Data writes actual row values, any personal, financial, or health data in those rows can end up in the session log. Logs are often readable by more people than the source data, and they can sit on shared servers.

Good practice is to enable it only in non-production environments, use a small, masked sample, switch it back to Normal immediately afterward, and purge or restrict the resulting logs. These are the same access-control and retention principles covered in our guide to improving data security compliance.

Using Tracing to Troubleshoot a Session

A simple, repeatable approach:

Start with Normal. Read the session log for the error, the transformation it names, and any skipped or rejected rows.
Isolate the transformation. Identify which transformation produces the wrong result, using row counts across stages.
Raise only that transformation. Set it to Verbose Data on a small data set in a test environment, rather than overriding the whole session.
Fix and verify. Correct the logic, then reconcile outputs against expected results, the same comparison approach covered in our guide to automating ETL testing with Python.
Revert. Return the transformation to Normal and remove any session-level override before promoting to production.

For performance work, the session property Collect Performance Data records performance details for a session, which you can review to tune it. Combine that with Verbose Initialization when examining cache-heavy transformations, and with the monitoring practices in our PowerCenter on AWS best practices.

Tracing and the PowerCenter Roadmap

PowerCenter is now in Informatica's maintenance mode, with new capability going into its cloud services. If you are planning a move, logging and monitoring are handled through the cloud platform's own tooling rather than PowerCenter session tracing, so budget time to re-establish your operational runbooks. See our PowerCenter vs IICS comparison, our IICS overview, and our wider look at traditional vs modern ETL. If the move involves procedural Oracle code, our guide to converting legacy PL/SQL to modern ETL applies as well.

Frequently Asked Questions

How many tracing levels does Informatica have?

Four: Terse, Normal, Verbose Initialization, and Verbose Data. The session-level None option simply means the mapping's settings apply.

What is the default tracing level?

Normal, for every transformation.

Does the tracing level affect performance?

Yes. Verbose levels add overhead, with Verbose Data the heaviest, while Terse gives a slight boost by logging the minimum.

Where do I override tracing for a whole session?

In the session's Config Object tab, using Override Tracing. It replaces the individual transformation settings.

Can Verbose Data expose sensitive information?

Yes. It logs each row that passes through a transformation, so sensitive values can appear in the session log. Use it only on masked or non-production data and secure the logs.

Get Help with Informatica Operations

The most common tracing mistake is leaving Verbose Data on after a debugging session ends. DataTerrain brings 17+ years and 400+ clients in ETL and data migration to Informatica engagements, from ETL to Informatica conversions and operations support to planned moves to IICS, with flexible working hours and no long-term binding contracts.

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