If you have more control over or knowledge of your load, you can safely go higher than 80%.
Eg when I was working at Google we carefully tagged our RPC calls by how 'sheddable' they were. More sheddable load gets dropped first. Or, from the opposite perspective: when important load is safely under 100%, which it is almost all the time in a well-designed system, we can also handle more optional, more sheddable load.
As a further aside, parts of the financial system work on similar principles:
If you have a flow of income over time, like from a portfolio of offices you are renting out, you can take the first 80% of dollars that come in on average every month and sell that very steady stream of income off for a high price.
The rest of income is much choppier. Sometimes you fail to rent everything. Sometimes occupants fall behind on rent. Sometimes a building burns down.
So you sell the rest off as cheaper equity. It's more risky, but also has more upside potential.
The more stable and diversified your business, the bigger proportion you can sell off as expensive fixed income.
If you have more control over or knowledge of your load, you can safely go higher than 80%.
Eg when I was working at Google we carefully tagged our RPC calls by how 'sheddable' they were. More sheddable load gets dropped first. Or, from the opposite perspective: when important load is safely under 100%, which it is almost all the time in a well-designed system, we can also handle more optional, more sheddable load.
As a further aside, parts of the financial system work on similar principles:
If you have a flow of income over time, like from a portfolio of offices you are renting out, you can take the first 80% of dollars that come in on average every month and sell that very steady stream of income off for a high price.
The rest of income is much choppier. Sometimes you fail to rent everything. Sometimes occupants fall behind on rent. Sometimes a building burns down.
So you sell the rest off as cheaper equity. It's more risky, but also has more upside potential.
The more stable and diversified your business, the bigger proportion you can sell off as expensive fixed income.