Cockroach Labs Estate economics What idle nodes, provisioned bytes and peak-sized bills cost, worked out from your estate.
  1. Nodes 6 baseline
  2. Avg CPU utilization 15.0% idle hardware
  3. Storage provisioned 120 GB 20 GB of data
  4. Est. monthly saving 0%

Step 1 of 8 - Virtualization

You're running an estate, not a cluster

Every cluster below was sized for its own peak, so every one of them idles.

Deployment model
Separate clusters One Private Host Cluster
2 standalone clusters, 6 nodes in totalcluster-0120% CPU3 nodescluster-0210% CPU3 nodesEstate before consolidation2 separate clusters of around 3 nodes each, 6 nodes in total, averaging 15.0% CPU utilization.
15%Average CPUAverage CPU CPU utilization15.0% of provisioned CPU is in use.

6 nodes running 7 vCPU of actual work.

The arithmetic, in full
StepWorkingResult
Provisioned today2 clusters of 3 nodes each, 6 in total x 8 vCPU48 vCPU
Mean demand48 vCPU x 15.0% estate average utilization (per-cluster 10.5% to 19.5%, sd 4.5%)7 vCPU
Aggregate peak7.2 vCPU x (1 + (2.23 - 1) / sqrt(2)), a pooled peak-to-mean of 1.86813 vCPU
Consolidated, sized once for the peakmax(3, ceil(13.5 vCPU / (8 vCPU x 37.5% target))) = max(3, ceil(4.48)); the mean sits well under that peak5 nodes, averaging 18.0%
Auto-scaled through the daythe pool follows the pooled curve in whole nodes, 30 minutes behind it, holding its size for 2 hours before shrinking4 nodes on average, at 22.5% CPU
Utilization across the day13.8% to 39.9% against a 37.5% setpoint: the pool runs hot while it's a bucket behind a rise, and cool while the cooldown is still holding capacity after a peak13.8%-39.9%

Assumptions

  • 8 vCPU per node. Standalone clusters are drawn around 3 nodes, snapped to an odd number for quorum and held between 3 and 15; in this estate they're all 3, because a spread centred on the end of that range has nowhere to go, for 6 nodes in total.
  • Each standalone cluster's CPU is a draw from a normal distribution centred on 15.0% and held between 0% and 100%; in this estate they run 10.5% to 19.5%, a 4.5-point standard deviation. The published band is 10-15% today against a 30-45% auto-scaled target, and this Private Host Cluster is set to 37.5%.
  • The Private Host Cluster floors at 3 nodes and must reach 5 at peak.
  • The auto-scaler sizes for what it saw 30 minutes ago and waits 2 hours before shrinking, so the pool averages 22.5% rather than sitting on its 37.5% setpoint.
  • Workloads are independent; consolidation moves where work runs, not how much there is.
What a virtual cluster gives an app team

Its own connection string, databases, schemas, users, roles and backups, and no visibility into the Private Host Cluster or any other virtual cluster.