workshop/aula-12/queries/useful-queries.md

# Queries PromQL Úteis

Queries prontas para uso no Grafana ou diretamente na API do Victoria Metrics.

## Como usar

### Via Grafana
1. Acesse Grafana → Explore
2. Selecione datasource "VictoriaMetrics"
3. Cole a query no editor

### Via API
```bash
# Port-forward
kubectl port-forward -n monitoring svc/vmsingle-vm-victoria-metrics-k8s-stack 8429:8429

# Query
curl "http://localhost:8429/api/v1/query?query=up"
```

---

## Storage / PVC

### Uso de PVC em porcentagem
```promql
kubelet_volume_stats_used_bytes / kubelet_volume_stats_capacity_bytes * 100
```

### PVCs acima de 80%
```promql
(kubelet_volume_stats_used_bytes / kubelet_volume_stats_capacity_bytes) > 0.8
```

### Espaço disponível por PVC (bytes)
```promql
kubelet_volume_stats_available_bytes
```

### Espaço disponível por PVC (GB)
```promql
kubelet_volume_stats_available_bytes / 1024 / 1024 / 1024
```

### Inodes disponíveis
```promql
kubelet_volume_stats_inodes_free / kubelet_volume_stats_inodes * 100
```

### PVCs que vão encher em 24h (previsão)
```promql
predict_linear(kubelet_volume_stats_available_bytes[6h], 24 * 3600) < 0
```

---

## CPU

### CPU por pod (cores)
```promql
sum(rate(container_cpu_usage_seconds_total{container!=""}[5m])) by (pod, namespace)
```

### CPU por namespace (cores)
```promql
sum(rate(container_cpu_usage_seconds_total{container!=""}[5m])) by (namespace)
```

### CPU por node (%)
```promql
100 - (avg by(instance) (rate(node_cpu_seconds_total{mode="idle"}[5m])) * 100)
```

### Top 10 pods por CPU
```promql
topk(10, sum(rate(container_cpu_usage_seconds_total{container!=""}[5m])) by (pod, namespace))
```

### Uso de CPU vs Request
```promql
sum(rate(container_cpu_usage_seconds_total{container!=""}[5m])) by (pod, namespace)
/
sum(kube_pod_container_resource_requests{resource="cpu"}) by (pod, namespace)
```

---

## Memória

### Memória por pod (bytes)
```promql
sum(container_memory_working_set_bytes{container!=""}) by (pod, namespace)
```

### Memória por namespace (GB)
```promql
sum(container_memory_working_set_bytes{container!=""}) by (namespace) / 1024 / 1024 / 1024
```

### Memória disponível por node (%)
```promql
(node_memory_MemAvailable_bytes / node_memory_MemTotal_bytes) * 100
```

### Top 10 pods por memória
```promql
topk(10, sum(container_memory_working_set_bytes{container!=""}) by (pod, namespace))
```

### Uso de memória vs Limit
```promql
sum(container_memory_working_set_bytes{container!=""}) by (pod, namespace)
/
sum(kube_pod_container_resource_limits{resource="memory"}) by (pod, namespace)
```

---

## Pods e Containers

### Pods restartando na última hora
```promql
sum(increase(kube_pod_container_status_restarts_total[1h])) by (pod, namespace) > 0
```

### Pods não Ready
```promql
kube_pod_status_ready{condition="false"}
```

### Pods em CrashLoopBackOff
```promql
kube_pod_container_status_waiting_reason{reason="CrashLoopBackOff"}
```

### Pods pendentes
```promql
kube_pod_status_phase{phase="Pending"}
```

### Containers OOMKilled
```promql
kube_pod_container_status_last_terminated_reason{reason="OOMKilled"}
```

### Total de pods por namespace
```promql
sum(kube_pod_info) by (namespace)
```

### Pods por node
```promql
sum(kube_pod_info) by (node)
```

---

## Deployments

### Deployments com réplicas indisponíveis
```promql
kube_deployment_status_replicas_unavailable > 0
```

### Deployments não atualizados
```promql
kube_deployment_status_observed_generation != kube_deployment_metadata_generation
```

### Proporção de réplicas disponíveis
```promql
kube_deployment_status_replicas_available / kube_deployment_spec_replicas
```

---

## Network

### Bytes recebidos por pod (rate)
```promql
sum(rate(container_network_receive_bytes_total[5m])) by (pod, namespace)
```

### Bytes enviados por pod (rate)
```promql
sum(rate(container_network_transmit_bytes_total[5m])) by (pod, namespace)
```

### Erros de rede por interface
```promql
sum(rate(node_network_receive_errs_total[5m])) by (instance, device)
```

### Conexões TCP por estado
```promql
node_netstat_Tcp_CurrEstab
```

---

## Nodes

### Nodes não Ready
```promql
kube_node_status_condition{condition="Ready",status="true"} == 0
```

### Pressão de memória
```promql
kube_node_status_condition{condition="MemoryPressure",status="true"} == 1
```

### Pressão de disco
```promql
kube_node_status_condition{condition="DiskPressure",status="true"} == 1
```

### Disco disponível por node (%)
```promql
(node_filesystem_avail_bytes{fstype!~"tmpfs|overlay"} / node_filesystem_size_bytes{fstype!~"tmpfs|overlay"}) * 100
```

### Load average (1 min)
```promql
node_load1
```

---

## Cluster Overview

### Total de pods Running
```promql
count(kube_pod_status_phase{phase="Running"})
```

### Total de namespaces
```promql
count(kube_namespace_created)
```

### Total de deployments
```promql
count(kube_deployment_created)
```

### Total de PVCs
```promql
count(kube_persistentvolumeclaim_info)
```

### Idade do cluster (dias)
```promql
(time() - min(kube_namespace_created{namespace="kube-system"})) / 86400
```

---

## Victoria Metrics

### Métricas sendo coletadas (por job)
```promql
count by (job) ({__name__!=""})
```

### Taxa de ingestão
```promql
sum(rate(vm_rows_inserted_total[5m]))
```

### Uso de disco do VM
```promql
vm_data_size_bytes
```

### Queries por segundo
```promql
sum(rate(vm_http_requests_total{path="/api/v1/query"}[5m]))
```

---

## Dicas

### Filtrar por namespace
```promql
# Adicione {namespace="meu-namespace"} a qualquer query
sum(container_memory_working_set_bytes{namespace="gitlab"}) by (pod)
```

### Excluir namespaces de sistema
```promql
{namespace!~"kube-system|argocd|monitoring|gitlab"}
```

### Agregar por label
```promql
sum by (label_app) (kube_pod_info)
```

### Ordenar resultados
```promql
sort_desc(sum(container_memory_working_set_bytes) by (namespace))
```

### Top N
```promql
topk(5, sum(rate(container_cpu_usage_seconds_total[5m])) by (pod))
```

### Valor no tempo (offset)
```promql
# Valor de 1 hora atrás
container_memory_working_set_bytes offset 1h
```

---

## Referências

- [PromQL Cheat Sheet](https://promlabs.com/promql-cheat-sheet/)
- [Victoria Metrics MetricsQL](https://docs.victoriametrics.com/metricsql/)
- [Grafana Dashboards](https://grafana.com/grafana/dashboards/)