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Tim's avatar
Tim
Data Integration
01-08-2026

What does an ElastiCube put in RAM

I heard "An Elasticube, once built and set to the Querying state, is designed to keep its data in memory for fast query access."

But I noticed that my cube is 90GB on disk, only 8GB in RAM after I refreshed one dashboard, and the RAM use goes jumped to 21GB when I opened a dashboard that queries a larger quantity of the cube's values.

So what's in RAM and what remains on disk? Cached query results? Indexes? Just the rows that have been used since the last build?

I'm curious because RAM use of large cubes is sometimes an issue; sometimes we redesign the cube to be smaller and sometimes we get more RAM. The more I understand, the better we can discuss and estimate.

Elasticube
memory
ram

1 Reply

  • HamzaJ's avatar
    HamzaJ
    Data Integration
    01-10-2026

    Hey Tim​ ,

    To my understanding;

    When a EC is build all imported data is stored on the disk (unless configured otherwise like S3). Whenever a cube is (re)build, the first time a user opens a dashboard, generates a report or does any action concerning data from the EC the EC is queried based on the data stored on the HDD. 

    This query result is stored in RAM. So for example if you have a dashboard with 10 different widgets , there will be 10 query results stored in the RAM (simply put, it does deserve some nuance). 

    This way when a (different) user opens the same dashboard the results are loaded quicker. However changing the result, for example with filters, will have longer loading times due to it not being cached (depending on server resources and datagroups configuration). Leading to an increase of RAM usages. In the end depending of the usage of Sisense and the specific EC loading data will be a mix of hdd and ram. The mix is mostly determined if users query same/similar data or if it is more volatile. 

    As far as I know Sisense handles cache in a 'smart' way meaning that not uses query results are dropped. 

    How it specifically/technically works on a detail level, is something I think Sisense can answer.

    Hamza