Solr upgrade from 6.5 to 8.7 (Keeping response time same or lower)

Job ID: 31201504

Budget: ₹750 – ₹1,250 INR

We have tried solr upgrade from 6.5 to 8.7. Upgrade was completed but the response time increased multi fold in solr 8.7. We kept the configuration same between 6.5 and 8.7, Still there was no improvement in response time.

Response time is of rest service which uses solr, Some times this service calls solr multiple time for a single request.
on 6.5 the response time is 450-500 ms
on 8.7 the response time is 750+ ms.

Index size- 95 GB
Heap 30 GB
Ram-96 GB
Polling Interval - 3 Hours
Standalone master-slave architecture.
Related categories: Apache Solr