Konata

• Konata is an instruction pipeline visualizer for traces in the Onikiri2-Kanata and gem5 O3PipeView formats.
  • Open the live demo.
• Starting with v1.0.0, Konata runs in the browser instead of as an Electron desktop application.
  • All trace processing remains local to the browser.
  • Local traces are never uploaded, and Konata makes no background network requests unless remote loading is explicitly requested.
  • Nearly all features from the desktop version are retained.
    • Like the desktop version, Konata can load trace files several gigabytes in size.
• The ASPLOS 2018 gem5 tutorial presentation provides an introduction to Konata.
• The Onikiri2-Kanata format represents pipeline behavior in greater detail than the gem5 O3PipeView format.

• Stable Web version: Open Konata Web stable, then select or drag and drop a plain-text, gzip-compressed, or Zstandard-compressed Kanata/O3PipeView trace.

• Downloaded version: Download the latest konata-v*.zip from GitHub Releases, extract it, and open index.html in a browser.

• Latest development version: Konata Web and konata-latest.zip are built from master.

• Remote server or WSL: Run the helper included in the downloaded version:

  ./konata.sh trace1.log.zst
  ./konata.sh trace1.log.zst trace2.log.zst

  The script prints the Konata URL and an SSH tunnel command. When running it on a remote server, run the printed SSH command on the local computer, then open the Konata URL in the local browser. Keep the script running while using Konata, and press Ctrl+C to stop it. Set KONATA_PORT before running the script to use another port.

Generate an O3PipeView trace with the gem5 O3 CPU model. This example follows the gem5 O3 Pipeline Viewer documentation:

./build/ARM/gem5.opt \
    --debug-flags=O3PipeView \
    --debug-start=<first tick of interest> \
    --debug-file=trace.out \
    configs/example/se.py \
    --cpu-type=detailed \
    --caches -c <path to binary> \
    -m <last cycle of interest>

Open trace.out using the Open menu or drag and drop it onto Konata. Enabling O3CPUAll alongside O3PipeView adds detailed CPU messages and instruction dependencies:

--debug-flags=O3PipeView,O3CPUAll

With O3CPUAll enabled, Konata associates messages with instructions using [sn:<serial number>]. Custom log messages with the same serial number are shown with the corresponding instruction.

• Open: Choose one or more traces, or drag and drop them onto the window.
• Recent and Reload: Reopen a recent trace or reload the current trace after its source file changes. If a change notice appears, choose Reload or Ignore.
• Search: Search the current trace with a regular expression. F3 and Shift+F3 move to the next and previous matches.
• Bookmark: Press 0–9 to go to a bookmark. Press Ctrl/Command+0–9 to save the current position and zoom in that slot.
• Stats: Show statistics for the current trace in a resizable dialog.
• View: Change the theme, pipeline colors, dependency arrows, lane layout, flushed-op visibility, and minimum lane heights used for drawing details. Custom colors can be edited from the Custom color scheme.
• Zoom: Change the zoom level. Zoom steps per 2× sets how many steps double or halve the view.
• Application log: Review parser warnings and other messages in a resizable pane at the bottom of the window.

• Drag the canvas to pan. Use a horizontal trackpad gesture to scroll horizontally.
• Use the mouse wheel or Up/Down keys to move through instructions vertically.
• Use Ctrl/Command+wheel, +/-, or Ctrl/Command+Up/Down to zoom.
• Double-click to zoom in. Shift+double-click to zoom out. Pinch with two pointers to zoom.
• Click an instruction label to align its fetch cycle with the left edge.
• Use Adjust position (the crosshair beside Reset) when the pipeline is outside the viewport. Adjust position preserves the zoom. Reset restores both the position and zoom.
• Click a tab to switch to it. Middle-click a tab to close it.

F1 or Ctrl/Command+Shift+P opens the command palette, which accepts these commands:

j  <op ID>    Jump to an operation ID
jr <RID>      Jump to a retired operation ID
f  <pattern>  Find a regular expression
l             Open the file picker

Command palette history, bookmarks, and view settings are saved between browser sessions.

Open two traces, select the tab to use as A, and choose Compare. Use A or B to inspect one trace with the other as a faint reference. Use Overlay to highlight differences. Dragging in A or B mode moves only that trace. Overlay mode moves both traces together. Align to A aligns them using a shared retired-operation ID when available.

Recent files, reload, and external-change detection require File System Access APIs supported by compatible Chromium-based browsers. Other browsers still support file selection and drag and drop. Remote traces opened with konata.sh can be reloaded manually. Automatic external-change detection is not available for them. Loading arbitrary URLs or paths is intentionally disabled.

Docker is the recommended development environment. Start a shell with the repository mounted at /workspace:

./docker/launch.sh

Run development commands from that shell:

make init          # Install dependencies
make               # Build the development Web application
make serve         # Start the Web development server
make production    # Build dist-web/index.html
make check         # Run the complete verification set
make benchmark-op-store

All build and test operations are Make targets. npm scripts are not used. make check uses Electron only to run the Web smoke test in sandboxed Chromium. Electron is not part of the application. To work without Docker, install Node.js 22.12 or later and run the same Make targets directly.

See Deployment and release for deployment to GitHub Pages and release procedures.

Copyright (C) 2016-2026 Ryota Shioya shioya@ci.i.u-tokyo.ac.jp

Konata is released under the BSD 3-Clause License. See LICENSE.md. The Web application includes third-party packages under their respective licenses. See THIRD_PARTY_LICENSES.md.