jstackfilter streamlines the analysis of noisy thread dumps produced by jstack. It highlights unusual or potentially problematic threads by eliminating duplicates and filtering out trivial or system threads. This helps you focus on what actually matters - finding the root cause of performance issues, deadlocks, or CPU spikes.

jstackfilter is available as a standalone GUI application, a command-line tool, an Eclipse IDE plugin, and a reusable Java library.

Jstackfilter does not rely on Java thread states (RUNNABLE, WAITING, etc...), as most of other trace analysis tools do. Instead it matches the stack frames against known database of idle thread patterns:

• revealing active threads even if they try to sleep to reduce the CPU load
• hiding irrelevant background threads even if they use CPU

In addition to a bundled database, user can supply their own patterns. A single click is enough to train Jstackfilter to ignore all background activity specific to an application you work with.

• Stacktrace Filtering: Removes duplicate and known-idle threads for concise output.
• Custom Idle Threads: Add your own filters to ignore threads common to your workloads.
• Supports Large Dumps: Handles even huge multi-megabyte thread dump files quickly.
• Human-Centric Output: Surfaces unusual or unique stack traces for faster debugging.
• Multiple Integration Modes: Use standalone GUI, CLI, as an Eclipse plugin, or as a library in your tools.
• Input Flexibility: Accepts thread dumps from live processes, files, or clipboard.
• Compatibility: Supports modern Java versions (≥11) and runs cross-platform.

A basic Swing graphical interface. Inspect running JVMs, jstack dumps from clipboard or files.

Filters Debug view of Eclipse JDT.

Use in scripts, or integrate in non-Java programs.

A JAR file to use in a Java program.