*A natural language search engine for your personal notes, transactions and images*
## Table of Contents
- [Features](#Features)
- [Demo](#Demo)
- [Description](#Description)
- [Analysis](#Analysis)
- [Architecture](#Architecture)
- [Setup](#Setup)
- [Clone](#Clone)
- [Configure](#Configure)
- [Run](#Run)
- [Use](#Use)
- [Upgrade](#Upgrade)
- [Troubleshooting](#Troubleshooting)
- [Miscellaneous](#Miscellaneous)
- [Development Setup](#Development-setup)
- [Setup on Local Machine](#Setup-on-local-machine)
- [Upgrade on Local Machine](#Upgrade-on-local-machine)
- [Run Unit Tests](#Run-unit-tests)
- [Performance](#Performance)
- [Query Performance](#Query-performance)
- [Indexing Performance](#Indexing-performance)
- [Miscellaneous](#Miscellaneous-1)
- [Acknowledgments](#Acknowledgments)
## Features
- **Natural**: Advanced Natural language understanding using Transformer based ML Models
- **Local**: Your personal data stays local. All search, indexing is done on your machine[\*](https://github.com/debanjum/khoj#miscellaneous)
- **Incremental**: Incremental search for a fast, search-as-you-type experience
- **Pluggable**: Modular architecture makes it relatively easy to plug in new data sources, frontends and ML models
- **Multiple Sources**: Search your Org-mode and Markdown notes, Beancount transactions and Photos
- **Multiple Interfaces**: Search using a [Web Browser](./src/interface/web/index.html), [Emacs](./src/interface/emacs/khoj.el) or the [API](http://localhost:8000/docs)
- The demo looks for the most relevant section in this readme and the [khoj.el readme](https://github.com/debanjum/khoj/tree/master/src/interface/emacs)
- Top result is what we are looking for, the [section to Install Khoj.el on Emacs](https://github.com/debanjum/khoj/tree/master/src/interface/emacs#installation)
### Analysis
- The results do not have any words used in the query
- *Based on the top result it seems the re-ranking model understands that Emacs is an editor?*
- The results incrementally update as the query is entered
- The results are re-ranked, for better accuracy, once user is idle
- Symptom: Errors out with \"Killed\" in error message
- Fix: Increase RAM available to Docker Containers in Docker Settings
- Refer: [StackOverflow Solution](https://stackoverflow.com/a/50770267), [Configure Resources on Docker for Mac](https://docs.docker.com/desktop/mac/#resources)
- Symptom: Errors out complaining about Tensors mismatch, null etc
- Mitigation: Delete content-type > image section from `docker_sample_config.yml`
## Miscellaneous
- The experimental [chat](localhost:8000/chat) API endpoint uses the [OpenAI API](https://openai.com/api/)
- It is disabled by default
- To use it add your `openai-api-key` to config.yml
- Semantic search using the bi-encoder is fairly fast at \<5 ms
- Reranking using the cross-encoder is slower at \<2s on 15 results. Tweak `top_k` to tradeoff speed for accuracy of results
- Applying explicit filters is very slow currently at \~6s. This is because the filters are rudimentary. Considerable speed-ups can be achieved using indexes etc
### Indexing performance
- Indexing is more strongly impacted by the size of the source data
- Indexing 100K+ line corpus of notes takes 6 minutes
- Indexing 4000+ images takes about 15 minutes and more than 8Gb of RAM
- Once <https://github.com/debanjum/khoj/issues/36> is implemented, it should only take this long on first run
### Miscellaneous
- Testing done on a Mac M1 and a \>100K line corpus of notes
- Search, indexing on a GPU has not been tested yet
## Acknowledgments
- [Multi-QA MiniLM Model](https://huggingface.co/sentence-transformers/multi-qa-MiniLM-L6-cos-v1), [All MiniLM Model](https://huggingface.co/sentence-transformers/all-MiniLM-L6-v2) for Text Search. See [SBert Documentation](https://www.sbert.net/examples/applications/retrieve_rerank/README.html)
- [OpenAI CLIP Model](https://github.com/openai/CLIP) for Image Search. See [SBert Documentation](https://www.sbert.net/examples/applications/image-search/README.html)
- Charles Cave for [OrgNode Parser](http://members.optusnet.com.au/~charles57/GTD/orgnode.html)
- [Org.js](https://mooz.github.io/org-js/) to render Org-mode results on the Web interface
- [Markdown-it](https://github.com/markdown-it/markdown-it) to render Markdown results on the Web interface
- Sven Marnach for [PyExifTool](https://github.com/smarnach/pyexiftool/blob/master/exiftool.py)