Mapper Size Plugin VS real Index Size

[gneves (Gustavo)]

Hello guys, hope you are doing well.

Im having a little problem, or not understanding something.

My problem is:

• In order to make a metrics dashboard about index sizes and other metrics, i have enabled Mapper Size Plugin.

• With just a normal Aggregation dashbaord, i have made a Sum of the "size field" (Scripted Field, in bytes) and lets say my index do have "26GB" of total size.

• But, when i go to stack monitoring > indices > i see that this index only have "5.4GB" On disk.

Am i doing something wrong, or there is a basic explanation for that?

Thank you for your help!!

[warkolm (Mark Walkom)]

@gneves

Hello guys

We aren't all guys

@gneves

With just a normal Aggregation dashbaord, i have made a Sum of the "size field" (Scripted Field, in bytes) and lets say my index do have "26GB" of total size.

At a guess are you sure that's not supposed to be 2.6GB? That'd be about 50% of what your index size is, which would account for the primary shard size.

[stephenb (Stephen Brown)]

Just driving by...BTW there by is a simple API to get this data

Index stats API | Elasticsearch Guide [7.15] | Elastic

[Christian_Dahlqvist]

The mapper size plugin indexes the size of the indexed JSON documents. These are then compressed and fields are indexed before being stored on disk. These operations will result in a different size index.