Konata

August 31, 2026 · View on GitHub

Konata is an instruction pipeline visualizer for traces in the Onikiri2-Kanata and gem5 O3PipeView formats. Open the live demo.

Since v1.0.0, Konata runs in the browser instead of as an Electron desktop application. Local traces remain in the browser and are never uploaded. Konata makes no background network requests unless remote loading is explicitly requested, and it can load trace files several gigabytes in size.

demo

Quick start

  • No installation is required to use the hosted version. Simply open Konata Web in a Web browser.

  • On a remote server or WSL, use the built-in Web server as follows:

    # Download and extract the latest development build.
curl -fLO https://shioyadan.github.io/Konata/konata-latest.zip
unzip -q konata-latest.zip
cd konata-latest

# On a remote host or WSL, start the launcher.
# It starts a local Web server on an available port and runs until Ctrl+C.
./konata.sh trace1.log.zst

    The launcher displays:

    Konata URL: http://127.0.0.1:30080/#name=trace1.log.zst
SSH tunnel: ssh -L 30080:127.0.0.1:30080 <host>
Press Ctrl+C to stop the server.

Usage

Generate and open a gem5 trace

Generate an O3PipeView trace with gem5's O3 CPU model. This gem5 v25.1 example uses the bundled legacy SE script to run an arbitrary binary:

./build/ALL/gem5.opt \
    --debug-flags=O3PipeView,Rename,MemDepUnit,LSQUnit \
    --debug-file=trace.log \
    configs/deprecated/example/se.py \
    --cpu-type=ArmO3CPU --caches --mem-size=512MiB \
    --cmd=<path-to-binary> --options="<program arguments>" \
    --maxinsts=<instruction-limit>
  • Rename adds register dependencies and information used to recover SMT thread IDs.
  • MemDepUnit adds memory-completion events, and LSQUnit adds load/store addresses.
  • Use only O3PipeView for a smaller trace, or O3PipeView,O3CPUAll for full troubleshooting.
  • Open m5out/trace.log using the Open menu or drag and drop it onto Konata.
  • Compress large traces with Zstandard (zstd trace.log); Konata opens .zst files directly.

Toolbar controls

  • 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.

Canvas and tabs

  • 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.

Command palette

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.

Trace comparison

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.

Browser limitations

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.

Distribution and updates

Update a downloaded copy

./konata-latest/konata.sh --update

The script downloads the latest tested development build from Konata Web and updates the extracted copy after confirmation.

Other ways to run

References

Development

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.

License

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.