Performance regression querying changes using _doc_ids filter #1737
When upgrading from v1.7.1 to v2.2.0 I noticed our replication was taking longer. I investigated further and found the problem was specifically in relation to the initial request for changes. We use the _doc_ids filter so we can replicate only certain documents and this has been stable and performant on the 1.x versions.
Steps to Reproduce
Use this node script to create a database and fill it with 1 million docs and then query it for specific IDs.
In my testing using the above script I got responses in 1 to 2ms on v1.7.1 and 2500 to 2600ms on 2.2.0.
This has affected real world performance for users trying to replicate their data.
What I've tried
The text was updated successfully, but these errors were encountered:
ok, I think I get this finally. Before 2.0, we had an optimization for _doc_ids and _design filter;
The clustered code for _changes does not use it.