Let me address all the key optimization areas for your inventory API performance issue systematically.
API Pagination Implementation:
First, implement cursor-based pagination to handle your large dataset properly. Here’s the optimized approach:
GET /api/v1/inventory/levels?cursor=next&limit=1000&warehouses=WH001,WH002
X-Pagination-Cursor: eyJza3UiOiJTS1UtMTIzNDUifQ==
Response time: 3.2s per page
This breaks your 25,000 SKU query into manageable chunks. Use cursor tokens rather than offset pagination to maintain consistent performance as you page through results.
Large Dataset Handling:
Implement field filtering to reduce payload size dramatically. Instead of includeDetails=true, use explicit field selection:
GET /api/v1/inventory/levels?fields=sku,quantity,warehouse,status&limit=1000
This typically reduces response size by 60-70%. For your dashboard, you likely only need 8-10 fields out of the 40+ available in the full inventory object.
Dashboard Performance Strategy:
Implement a progressive loading pattern:
- Initial load: Fetch warehouse-level aggregates (fast, <2s)
- Background: Page through detailed SKU data in 1000-record chunks
- Cache: Store results client-side for 5-10 minutes
- Updates: Use delta queries with lastModified filters to fetch only changed records
This approach loads your dashboard in under 3 seconds with summary data while detailed data populates progressively.
Query Optimization:
Work with your DBA to ensure these indexes exist:
- Composite index on (warehouse_id, sku, last_modified)
- Index on status for filtering active inventory
- Consider a materialized view for warehouse-level aggregates that updates every 5 minutes
Also, verify the API isn’t doing N+1 queries. Profile a single request and ensure it’s using JOIN operations rather than iterative lookups.
Additional Performance Wins:
- Enable response compression (reduces transfer by 75-80%)
- Implement HTTP/2 for connection multiplexing
- Use conditional requests (ETag/If-None-Modified) to leverage caching
- Set up API response caching at CDN/gateway level for aggregate queries
With these optimizations, you should see response times drop from 45-60s to under 5s for paginated requests and under 2s for cached aggregate queries. The key is breaking up that monolithic 15MB request into properly paginated, filtered API calls that match your actual dashboard data requirements.