Recommended Merge Option

Elastic Stack Elasticsearch
1

Guys,
In a system where u could expect a decent rate of update request, say 10% of overall documents getting updated daily, what is the merge setting for -

Merge | Elasticsearch Guide [8.11] | Elastic
index.merge.policy.reclaim_deletes_weight

one would recommend so we have the deleted document count very much under control. We have seen in cases, the deleted document count goes up to 30% and stays there. We end up doing periodic expunge delete.

2

Are the all in larger segments? I've seen similar issues with large segments.

3

yes, mostly

4

replying so thread becomes latest and people can share views about this one.

5

Be very careful increasing this setting too much: it can cause way too much merging to happen.

This blog post has more details: https://www.elastic.co/blog/lucenes-handling-of-deleted-documents

6

I see. thanks! This is good info.