Compression ratio

Thanks for pointing us in the right direction. This solves the purpose well.

For getting the total ingested volume, I am using the following query:

GET my_index-2019.01.20/_search
{
  "query": {
    "match_all": {}
  },
  "aggs": {
    "sizes": {
      "sum": {
        "field": "_size"
      }
    }
  }
}

The only problem is for large indices (65gb primary volume), the request times out.