I have a data base of 1.3m docs, ~8gb.
I have recently moved from 6.0.0 to 6.2.4 and had a terrible slow down of 2-5 times in searches. From around 300-500ms per search to 1000-2000ms.
My cluster has one node, one shard and one index.
I didn't upgrade the cluster, I reinstalled from scratch. After seeing the slowdown I reinstalled 6.0.0 and searches accelerated again. All indexes had the exact same settings.
It's almost all text search and high-lightning (match and match_phrase)
Any ideas why this is happening?