JSTACK
Generated by scripts/gen-format-pages.py from docs/data/format-metadata/, FILE_FORMATS.csv and docs/formats-master.csv. Do not edit by hand: change the source, then run the script.
JVM jstack Preview.
At a glance
| Purpose | A JVM thread dump (jstack or kill -3 output): one block per thread with its state and stack. |
| Extensions | .jstack |
| Poka parser | poka-jstack |
| Viewer | poka-tree-viewer |
| Depth tier | Parser with a shared viewer (see Depth tiers) |
| Breadth tier | B3 Core (see Breadth tiers) |
How much Poka reads
B3 Core. Only the main content type or types are decoded (for example geometry but not materials, layers or annotations, or only one version family). The list of gaps is substantial.
Confidence: medium (the reviewer read the code). Basis: Reviewed 2026-10-26: read parsers/poka-jstack/src/main.rs (404 lines) and plugin.json. No unit tests or tests/samples.rs; the corpus has 1.jstack, read by no test. Covers .jstack and .threaddump. The tree shows the JVM version, timestamp, thread and daemon counts and any deadlock, groups the threads by state, and lists each thread with priority, IDs, state and its top one or two frames. Judgement: B3: every thread is listed with its state, but the stacks are cut to their top frames.
What Poka does not read
- Only the top one or two frames of each stack are shown
- Held and awaited locks are not shown per thread (judgement from the code)
- The heap summary and JNI references at the end are not read
- Caps of 500 threads and 3,000 nodes; files over 256 MiB are cut (flagged)
Libraries
Libraries Poka uses or has assessed for this format, with the status, licence and language the registry records.
- jthreaddump (candidate; MIT; Java; https://github.com/parttimenerd/jthreaddump) — Parses jstack and jcmd thread dumps (threads, locks, deadlocks); parsing only, Java 17+
Sources
- parsers/poka-jstack/src/main.rs
- parsers/poka-jstack/plugin.json