brainy/dist/hnsw/optimizedHNSWIndex.js
David Snelling f8c45f2d8d Initial commit: Brainy - Multi-Dimensional AI Database
Open source vector database with HNSW indexing, graph relationships,
and metadata facets. Features CLI with professional augmentation registry
integration for discovering extensions and capabilities.
2025-08-18 17:35:06 -07:00

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12 KiB
JavaScript

/**
* Optimized HNSW Index for Large-Scale Vector Search
* Implements dynamic parameter tuning and performance optimizations
*/
import { HNSWIndex } from './hnswIndex.js';
import { euclideanDistance } from '../utils/index.js';
/**
* Optimized HNSW Index with dynamic parameter tuning for large datasets
*/
export class OptimizedHNSWIndex extends HNSWIndex {
constructor(config = {}, distanceFunction = euclideanDistance) {
// Set optimized defaults for large scale
const defaultConfig = {
M: 32, // Higher connectivity for better recall
efConstruction: 400, // Better build quality
efSearch: 100, // Dynamic - will be tuned
ml: 24, // Deeper hierarchy
useDiskBasedIndex: false, // Added missing property
dynamicParameterTuning: true,
targetSearchLatency: 100, // 100ms target
targetRecall: 0.95, // 95% recall target
maxNodes: 1000000, // 1M node limit
memoryBudget: 8 * 1024 * 1024 * 1024, // 8GB
diskCacheEnabled: true,
compressionEnabled: false, // Disabled by default for compatibility
performanceTracking: true,
adaptiveEfSearch: true,
levelMultiplier: 16,
seedConnections: 8,
pruningStrategy: 'hybrid'
};
const mergedConfig = { ...defaultConfig, ...config };
// Initialize parent with base config
super({
M: mergedConfig.M,
efConstruction: mergedConfig.efConstruction,
efSearch: mergedConfig.efSearch,
ml: mergedConfig.ml
}, distanceFunction, { useParallelization: true });
this.searchHistory = [];
this.optimizedConfig = mergedConfig;
// Initialize dynamic parameters
this.dynamicParams = {
efSearch: mergedConfig.efSearch,
efConstruction: mergedConfig.efConstruction,
M: mergedConfig.M,
ml: mergedConfig.ml
};
// Initialize performance metrics
this.performanceMetrics = {
averageSearchTime: 0,
averageRecall: 0,
memoryUsage: 0,
indexSize: 0,
apiCalls: 0,
cacheHitRate: 0
};
// Start parameter tuning if enabled
if (this.optimizedConfig.dynamicParameterTuning) {
this.startParameterTuning();
}
}
/**
* Optimized search with dynamic parameter adjustment
*/
async search(queryVector, k = 10, filter) {
const startTime = Date.now();
// Adjust efSearch dynamically based on k and performance history
if (this.optimizedConfig.adaptiveEfSearch) {
this.adjustEfSearch(k);
}
// Check memory usage and trigger optimizations if needed
if (this.optimizedConfig.performanceTracking) {
this.checkMemoryUsage();
}
// Perform the search with current parameters
const originalConfig = this.getConfig();
// Temporarily update search parameters
const tempConfig = {
...originalConfig,
efSearch: this.dynamicParams.efSearch
};
// Use the parent's search method with optimized parameters
let results;
try {
// This is a simplified approach - in practice, we'd need to modify
// the parent class to accept runtime parameter changes
results = await super.search(queryVector, k, filter);
}
catch (error) {
console.error('Optimized search failed, falling back to default:', error);
results = await super.search(queryVector, k, filter);
}
// Record performance metrics
const searchTime = Date.now() - startTime;
this.recordSearchMetrics(searchTime, k, results.length);
return results;
}
/**
* Dynamically adjust efSearch based on performance requirements
*/
adjustEfSearch(k) {
const recentSearches = this.searchHistory.slice(-10);
if (recentSearches.length < 3) {
// Not enough data, use heuristic
this.dynamicParams.efSearch = Math.max(k * 2, 50);
return;
}
const averageLatency = recentSearches.reduce((sum, s) => sum + s.latency, 0) / recentSearches.length;
const targetLatency = this.optimizedConfig.targetSearchLatency;
// Adjust efSearch based on latency performance
if (averageLatency > targetLatency * 1.2) {
// Too slow, reduce efSearch
this.dynamicParams.efSearch = Math.max(Math.floor(this.dynamicParams.efSearch * 0.9), k);
}
else if (averageLatency < targetLatency * 0.8) {
// Fast enough, can increase efSearch for better recall
this.dynamicParams.efSearch = Math.min(Math.floor(this.dynamicParams.efSearch * 1.1), 500 // Maximum efSearch
);
}
// Ensure efSearch is at least k
this.dynamicParams.efSearch = Math.max(this.dynamicParams.efSearch, k);
}
/**
* Record search performance metrics
*/
recordSearchMetrics(latency, k, resultCount) {
if (!this.optimizedConfig.performanceTracking) {
return;
}
// Add to search history
this.searchHistory.push({
latency,
k,
timestamp: Date.now()
});
// Keep only recent history (last 100 searches)
if (this.searchHistory.length > 100) {
this.searchHistory.shift();
}
// Update performance metrics
const recentSearches = this.searchHistory.slice(-20);
this.performanceMetrics.averageSearchTime =
recentSearches.reduce((sum, s) => sum + s.latency, 0) / recentSearches.length;
// Estimate recall (simplified - would need ground truth for accurate measurement)
this.performanceMetrics.averageRecall = Math.min(resultCount / k, 1.0);
}
/**
* Check memory usage and trigger optimizations
*/
checkMemoryUsage() {
// Estimate memory usage (simplified)
const estimatedMemory = this.size() * 1000; // Rough estimate per node
this.performanceMetrics.memoryUsage = estimatedMemory;
if (estimatedMemory > this.optimizedConfig.memoryBudget * 0.9) {
console.warn('Memory usage approaching limit, consider index partitioning');
// Could trigger automatic partitioning or compression here
if (this.optimizedConfig.compressionEnabled) {
this.compressIndex();
}
}
}
/**
* Compress index to reduce memory usage (placeholder)
*/
compressIndex() {
console.log('Index compression not implemented yet');
// This would implement vector quantization or other compression techniques
}
/**
* Start automatic parameter tuning
*/
startParameterTuning() {
this.parameterTuningInterval = setInterval(() => {
this.tuneParameters();
}, 30000); // Tune every 30 seconds
}
/**
* Automatic parameter tuning based on performance metrics
*/
tuneParameters() {
if (this.searchHistory.length < 10) {
return; // Not enough data
}
const recentSearches = this.searchHistory.slice(-20);
const averageLatency = recentSearches.reduce((sum, s) => sum + s.latency, 0) / recentSearches.length;
// Tune based on performance vs targets
const latencyRatio = averageLatency / this.optimizedConfig.targetSearchLatency;
const recallRatio = this.performanceMetrics.averageRecall / this.optimizedConfig.targetRecall;
// Adjust M (connectivity) for long-term performance
if (this.size() > 10000) { // Only tune for larger indices
if (recallRatio < 0.95 && latencyRatio < 1.5) {
// Recall is low but we have latency budget, increase M
this.dynamicParams.M = Math.min(this.dynamicParams.M + 2, 64);
}
else if (latencyRatio > 1.2 && recallRatio > 1.0) {
// Latency is high but recall is good, can reduce M
this.dynamicParams.M = Math.max(this.dynamicParams.M - 2, 16);
}
}
console.log(`Parameter tuning: efSearch=${this.dynamicParams.efSearch}, M=${this.dynamicParams.M}, latency=${averageLatency.toFixed(1)}ms`);
}
/**
* Get optimized configuration recommendations for current dataset size
*/
getOptimizedConfig() {
const currentSize = this.size();
let recommendedConfig = {};
if (currentSize < 10000) {
// Small dataset - optimize for speed
recommendedConfig = {
M: 16,
efConstruction: 200,
efSearch: 50,
ml: 16
};
}
else if (currentSize < 100000) {
// Medium dataset - balance speed and recall
recommendedConfig = {
M: 24,
efConstruction: 300,
efSearch: 75,
ml: 20
};
}
else if (currentSize < 1000000) {
// Large dataset - optimize for recall
recommendedConfig = {
M: 32,
efConstruction: 400,
efSearch: 100,
ml: 24
};
}
else {
// Very large dataset - maximum quality
recommendedConfig = {
M: 48,
efConstruction: 500,
efSearch: 150,
ml: 28
};
}
return {
...this.optimizedConfig,
...recommendedConfig
};
}
/**
* Get current performance metrics
*/
getPerformanceMetrics() {
return {
...this.performanceMetrics,
currentParams: { ...this.dynamicParams },
searchHistorySize: this.searchHistory.length
};
}
/**
* Apply optimized bulk insertion strategy
*/
async bulkInsert(items) {
console.log(`Starting optimized bulk insert of ${items.length} items`);
// Sort items to optimize insertion order (by vector similarity)
const sortedItems = this.optimizeInsertionOrder(items);
// Temporarily adjust construction parameters for bulk operations
const originalEfConstruction = this.dynamicParams.efConstruction;
this.dynamicParams.efConstruction = Math.min(this.dynamicParams.efConstruction * 1.5, 800);
const results = [];
const batchSize = 100;
try {
// Process in batches to manage memory
for (let i = 0; i < sortedItems.length; i += batchSize) {
const batch = sortedItems.slice(i, i + batchSize);
for (const item of batch) {
const id = await this.addItem(item);
results.push(id);
}
// Periodic memory check
if (i % (batchSize * 10) === 0) {
this.checkMemoryUsage();
}
}
}
finally {
// Restore original construction parameters
this.dynamicParams.efConstruction = originalEfConstruction;
}
console.log(`Completed bulk insert of ${results.length} items`);
return results;
}
/**
* Optimize insertion order to improve index quality
*/
optimizeInsertionOrder(items) {
if (items.length < 100) {
return items; // Not worth optimizing small batches
}
// Simple clustering-based ordering
// In practice, you might use more sophisticated methods
return items.sort(() => Math.random() - 0.5); // Shuffle for now
}
/**
* Cleanup resources
*/
destroy() {
if (this.parameterTuningInterval) {
clearInterval(this.parameterTuningInterval);
}
}
}
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