Cockroach Labs Estate economics What idle nodes, provisioned bytes and peak-sized bills cost, worked out from your estate.

Estate summary

  1. Nodes 127 baseline
  2. Avg CPU utilization 15.0% idle hardware
  3. Storage provisioned 1.5 TB 250 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.

25 standalone clusters, 127 nodes in totalcluster-0110% CPU5 nodescluster-025% CPU5 nodescluster-0321% CPU5 nodescluster-0417% CPU5 nodescluster-059% CPU5 nodescluster-0614% CPU5 nodescluster-0710% CPU3 nodescluster-0817% CPU5 nodescluster-0914% CPU5 nodescluster-1012% CPU5 nodescluster-1110% CPU5 nodescluster-1218% CPU5 nodescluster-1319% CPU5 nodescluster-1424% CPU5 nodescluster-1512% CPU5 nodescluster-1613% CPU5 nodescluster-1717% CPU5 nodescluster-1824% CPU5 nodescluster-1913% CPU5 nodescluster-2014% CPU5 nodescluster-2112% CPU7 nodescluster-2216% CPU5 nodescluster-2319% CPU5 nodescluster-2415% CPU7 nodescluster-2518% CPU5 nodesEstate before consolidation25 separate clusters of around 5 nodes each, 127 nodes in total, averaging 15.0% CPU utilization.
15%Average CPUAverage CPU CPU utilization15.0% of provisioned CPU is in use.

127 nodes running 152 vCPU of actual work.

The arithmetic, in full
StepWorkingResult
Provisioned today25 clusters totalling 127 nodes (drawn around 5, 3 to 7) x 8 vCPU1016 vCPU
Mean demand1016 vCPU x 15.0% estate average utilization (per-cluster 5.3% to 24.2%, sd 4.5%)152 vCPU
Aggregate peak152.4 vCPU x (1 + (2.23 - 1) / sqrt(25)), a pooled peak-to-mean of 1.246190 vCPU
Consolidated, sized once for the peakmax(3, ceil(189.8 vCPU / (8 vCPU x 37.5% target))) = max(3, ceil(63.28)); the mean sits well under that peak64 nodes, averaging 29.8%
Auto-scaled through the daythe pool follows the pooled curve in whole nodes, 30 minutes behind it, holding its size for 2 hours before shrinking53 nodes on average, at 35.9% CPU
Utilization across the day30.3% to 39.1% 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 peak30.3%-39.1%

Assumptions

  • 8 vCPU per node. Standalone clusters are drawn around 5 nodes, snapped to an odd number for quorum and held between 3 and 15; in this estate they run 3 to 7, a 0.7-node standard deviation, for 127 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 5.3% to 24.2%, 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 64 at peak.
  • The auto-scaler sizes for what it saw 30 minutes ago and waits 2 hours before shrinking, so the pool averages 35.9% 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.