Calculate the effective storage space for data

Hello,

Let’s say I have 6 nodes in my cluster, each with a disk of 1TB for cockroachdb storage, allwithing a single datacenter & availability zone, for simplicity.
My usable capacity in the dashboard will most likely be 6TB, but with a num_replicas of 5, how much actual data will I be able to store in those 6TB?

The 6TB available throughout the cluster will also be used for replication & system data.
Is the formula <total capacity>/num_replicas, in this case 1.2TB, a good approximation?

Hello @paullik, welcome to the forum.

While there are other factors to consider with replication, you are on the right track in terms of estimating capacity. size of data * number of replicas is a good way to think about how much storage you will need. So your total capacity / number of replicas is a good way to think about it.

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