Alexander Abakumov
15e744da49
- Added comprehensive course structure with 11 modules - Included theoretical content, practical examples, and tasks - Multi-language code examples (Java, Rust, Node.js, Python) - Detailed analysis of architectural approaches and trade-offs - Complete caching strategies documentation - Architecture examples from real-world systems (Twitter, Netflix, Uber) - Structured navigation and learning path - Ready for educational use
2.6 KiB
2.6 KiB
SLI/SLO/SLA
Навигация
SLI (Индикатор уровня сервиса)
SLI — метрика, которая измеряет качество сервиса.
Примеры SLI:
- Availability:
successful_requests / total_requests - Latency:
requests_completed_within_threshold / total_requests - Throughput:
successful_requests_per_second
@Component
public class SLICalculator {
public double calculateAvailability(String service, Duration window) {
Counter successfulRequests = Counter.builder("requests.successful")
.tag("service", service)
.register(meterRegistry);
Counter totalRequests = Counter.builder("requests.total")
.tag("service", service)
.register(meterRegistry);
double successful = successfulRequests.count();
double total = totalRequests.count();
return total > 0 ? successful / total : 0.0;
}
public double calculateLatency(String service, Duration threshold) {
Timer requestTimer = Timer.builder("request.duration")
.tag("service", service)
.register(meterRegistry);
// логика расчета латентности
return 0.95; // пример
}
}
SLO (Цель уровня сервиса)
SLO — целевое значение для SLI.
Примеры SLO:
- Availability: 99.9% uptime
- Latency: 95% of requests < 200ms
- Error Rate: < 0.1% errors
@Component
public class SLOMonitor {
private final Map<String, SLO> slos = Map.of(
"availability", new SLO("availability", 0.999, "99.9% uptime"),
"latency", new SLO("latency", 0.95, "95% < 200ms"),
"error_rate", new SLO("error_rate", 0.001, "< 0.1% errors")
);
public boolean checkSLO(String sloName, double currentValue) {
SLO slo = slos.get(sloName);
return currentValue >= slo.getTarget();
}
}
SLA (Соглашение об уровне сервиса)
SLA — соглашение с клиентами о качестве сервиса.
Компоненты SLA:
- Service Description — описание сервиса
- Performance Metrics — метрики производительности
- Availability Targets — цели доступности
- Remediation — меры по устранению нарушений