Would turning off swap require extra configuration

[hasancansaral]

I have a 3 node cluster, all master eligible and all having 4 cores, 16gb memory. I have 2 read/write indexes with none of them above 1 GB/1 million documents. Each index is 1 primary shard and 2 replicas.

I've recently noticed that 2 nodes were swapping. I turned on swap permanently and performed a rolling restart. All my indices and cluster have green health now.

1. Do I have to change anything (regarding heap size, etc.) or would Elasticsearch calculate a new heap size after the swapoff? Current memory usage is around 9GB per node at the moment.
2. During rolling restart of the cluster, I noticed a change in docs.deleted. I assume that this is related to shards relocating, and nothing to be worried about. Am I correct?

A little related final question;
3. When the docs.deleted go above 50% of the number of documents in index, I see it reset. (I do not perform a _forcemerge or expunge deletes for that matter. This is the expected behaviour right?

Thanks.

[warkolm (Mark Walkom)]

Welcome to our community!

1. Nope, nothing changes after you do this.
2. Nope, that would be either updates or someone deleting docs.
3. It's likely to be a merge

[hasancansaral]

Hi Mark, thank you for your reply. All is good now.