Step 8 of 8 - Summary
Everything you changed, added up
Seven pages of controls come down to one number: what this estate would pay against what it pays today. Here's where that number comes from, and what you haven't switched on yet.
Virtualization
One Private Host Cluster
Estimated saving against your estate today
58.5%
All of it from virtualization, leaving this estate at 41.5% of what it pays today. The switches still off are worth 4.9% more from here.
- From virtualization
- 58.5%
- From storage
- 0.0%
- Still on the table
- 4.9%
75 nodes become 31. That one movement is the arithmetic. The rest of the site is why it's safe to make.
- One Private Host Cluster - on, worth 58.5%; 75 nodes become 31 for the same work, at 36.3% CPU instead of 15.0%.
- Plenum - off, worth 4.8% more taken in this order; 1.0 TB reaches the meter instead of 1.5 TB, and the nodes stop renting block storage to hold it.
- 80% of the data tiered cold - off, worth 0.1% more taken in this order; cold data keeps 1 copy in object storage and none on disk: 400 GB billed instead of 1.0 TB.
| Step | Working | Result |
|---|---|---|
| Your estate today | separate clusters on block storage: the baseline every percentage on this site is measured against | 100% |
| One Private Host Cluster | switched on; 75 nodes become 31 for the same work, at 36.3% CPU instead of 15.0% | -58.5% |
| Plenum | not switched on; 1.0 TB reaches the meter instead of 1.5 TB, and the nodes stop renting block storage to hold it | -4.8% |
| 80% of the data tiered cold | not switched on; cold data keeps 1 copy in object storage and none on disk: 400 GB billed instead of 1.0 TB | -0.1% |
| What you're set up for | the switches you've turned on, against the baseline | 41.5% |
| Still on the table | the switches you haven't, priced from where you're standing | -4.9% |
| With everything switched on | every switch on | 36.6% |
How this is added up
- The baseline is the estate you described on the front page, bought the way it's bought today: 25 separate clusters on block storage. Every percentage on this page and every percentage in the bar at the top of the screen is measured against that one number.
- These switches aren't independent - the storage layer changes what a node costs, and consolidation changes how many nodes there are to charge for - so a total can only be split along some order. This one starts at the baseline and climbs through the switches you've already thrown before it reaches the ones you haven't. That's what makes the switched-on rows add up to exactly the 58.5% in the bar above. Each remaining row is then priced from the row above it rather than from the baseline, so they add up to the 4.9% that's left rather than to more than there is: throw one on its own and it's worth more than the line here says, because it would be collecting overlap the row above it has already claimed.
- Nothing on this page prices the rest of the argument. Fewer bad days from a runaway neighbour, a scale-out that finishes in seconds instead of hours, and a node loss that doesn't move data are all worth something, and none of them are worth a percentage this model can defend.
- The rates behind the arithmetic are derived from a design-doc cost model at 200-node scale, not from list prices and not from final pricing. Illustrative, not measured. The claim is the ratio, whatever the bill turns out to be.
Every figure here follows the estate you described. Change it and this page changes with it - or go back through the pages and read why any one of these switches is safe to throw.