boosting performance for jekyll client side search
Why Performance Matters in Client-Side Search
Client-side search relies on JavaScript and JSON indexes loaded into the browser. As your knowledge base grows, search responsiveness and page load times can degrade if not optimized. Enhancing performance leads to smoother user experiences and lower bounce rates.
Common Performance Bottlenecks
- Large JSON index files increasing initial load time
- Slow parsing and processing of search data in JavaScript
- Unoptimized UI updates causing jank or delays
- Repeated fetching of the index file on each page visit
Strategies for Effective Caching
Caching reduces redundant network requests and speeds up subsequent searches.
HTTP Cache-Control Headers
Ensure your search.json file is served with proper cache headers via GitHub Pages or CDN settings to allow long-lived caching.
LocalStorage Caching
Use localStorage to store the parsed search index on the client, avoiding repeated downloads.
async function loadSearchIndex() {
const cached = localStorage.getItem('searchIndex');
if (cached) {
return JSON.parse(cached);
} else {
const response = await fetch('/search.json');
const data = await response.json();
localStorage.setItem('searchIndex', JSON.stringify(data));
return data;
}
}
Lazy Loading and Code Splitting
Only load search scripts and data when the user interacts with the search UI.
- Defer loading the search library until the search box is focused
- Use dynamic imports or script tags injected on demand
Optimizing JSON Index Size
Smaller indexes load and parse faster.
- Strip unnecessary fields or verbose content
- Compress JSON during build with tools or plugins
- Consider using more compact formats like JSONL or binary (advanced)
Debouncing Search Input
Prevent firing a search on every keystroke by debouncing input events.
let debounceTimeout;
searchInput.addEventListener('input', () => {
clearTimeout(debounceTimeout);
debounceTimeout = setTimeout(() => {
performSearch(searchInput.value);
}, 300);
});
Profiling and Measuring Performance
Use browser dev tools to profile script execution and identify slow spots.
- Monitor network waterfall for asset load times
- Use JavaScript CPU profiling to detect heavy functions
- Track frame rates and UI responsiveness
Case Study: Performance Gains in a Medium-Sized Knowledge Base
By implementing localStorage caching and lazy loading search assets, a knowledge base of 500+ pages reduced initial search load time by 70%, with near-instant searches thereafter. Debounced inputs improved UI responsiveness significantly.
Conclusion
Optimizing performance for client-side search in Jekyll knowledge bases requires a combination of caching, code management, and thoughtful UI handling. These improvements lead to fast, responsive, and enjoyable user experiences on fully static GitHub Pages sites.