An error budget is the allowed amount of failure implied by a service level objective. It equals 100% minus the SLO target, measured over the same window. If the SLO is 99.9% availability, the budget is the remaining 0.1%.
Why it matters
The budget turns reliability into a shared, measurable resource instead of an argument. While budget remains, a team can ship risky changes, run experiments or perform maintenance. When it is spent, the team shifts effort to stability work until the window recovers. This idea comes from site reliability engineering practice and gives product and operations teams a neutral rule for deciding between speed and safety.
Example
With a 99.9% SLO over 30 days:
30 days x 24 h x 60 min = 43,200 minutes
budget = 43,200 x 0.001 = 43.2 minutes of allowed downtimeA 20-minute outage consumes about 46% of the budget. A second 30-minute outage would exhaust it and put the SLO at risk.
Common mistakes
- Treating the budget as a target to use up. It is a limit, not a quota.
- Counting only full outages and ignoring slow or partially failing requests, if the SLI includes them.
- Setting an SLO of 100%, which leaves a budget of zero and makes any change a breach.
- Never reviewing burn rate, so the budget disappears early in the window unnoticed.
Related
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यह पेज सामान्य जानकारी है, जिसे हमारी संपादकीय टीम ने लिखा है और दस्तावेज़ीकरण बदलने पर अपडेट किया जाता है। सर्वर और प्रदाता अलग-अलग होते हैं, इसलिए बदलाव पहले सुरक्षित तरीके से जाँचें। देखें: संपादकीय नीति और अस्वीकरण.