resultsCache is not used

[patsevanton]

Describe the bug
resultsCache is not used

To Reproduce
Steps to reproduce the behavior:

1. Loki version 6.27.0
2. Promtail version 6.15.3

Expected behavior
resultsCache is used

Environment:

• Infrastructure: Kubernetes
• Deployment tool: helm

Screenshots, Promtail config, or terminal output

---
apiVersion: source.toolkit.fluxcd.io/v1
kind: HelmRepository
metadata:
  name: grafana
  namespace: loki-core
spec:
  interval: 24h
  url: https://grafana.github.io/helm-charts

---
apiVersion: helm.toolkit.fluxcd.io/v2
kind: HelmRelease
metadata:
  name: loki
  namespace: loki-core
spec:
  interval: 30m
  install:
    remediation:
      retries: 3
  chart:
    spec:
      chart: loki
      version: 6.27.0
      sourceRef:
        kind: HelmRepository
        name: grafana
  values:
    deploymentMode: Distributed
    global:
      image:
        registry: "harbor.corp/dockerhub"
    .globalExtra: &globalExtra
      extraArgs:
        - "-config.expand-env=true"
      extraEnv:
        - name: S3_ACCESS_KEY_ID
          valueFrom:
            secretKeyRef:
              name: loki-s3
              key: S3_ACCESS_KEY_ID
        - name: S3_SECRET_ACCESS_KEY
          valueFrom:
            secretKeyRef:
              name: loki-s3
              key: S3_SECRET_ACCESS_KEY
      tolerations:
        - key: "role"
          operator: "Equal"
          value: "loki"
          effect: "NoSchedule"
      nodeSelector:
        role: loki
    gateway:
      enabled: false
    ingress:
      enabled: true
      ingressClassName: nginx
      annotations:
        cert-manager.io/cluster-issuer: "cluster-issuer"
        nginx.ingress.kubernetes.io/proxy-read-timeout: "600"
        nginx.ingress.kubernetes.io/proxy-send-timeout: "600"
      hosts:
        - loki-core-v2.corp
      serviceMonitor:
        enabled: true
    compactor:
      enabled: true
      replicas: 1
      <<: *globalExtra
      persistence:
        enabled: true
        claims:
          - name: data
            size: 50Gi
            storageClass: yc-network-ssd
      resources:
        requests:
          memory: "2Gi"
          cpu: "800m"
        limits:
          memory: "2Gi"
    distributor:
      <<: *globalExtra
      replicas: 1
      autoscaling:
        enabled: true
        minReplicas: 3
        maxReplicas: 7
        targetCPUUtilizationPercentage: 70
        targetMemoryUtilizationPercentage: 70
      resources:
        requests:
          memory: "260Mi"
          cpu: "300m"
        limits:
          memory: "260Mi"
      maxUnavailable: 1
      affinity:
        podAntiAffinity:
          requiredDuringSchedulingIgnoredDuringExecution: []
          preferredDuringSchedulingIgnoredDuringExecution:
            - weight: 99
              podAffinityTerm:
                labelSelector:
                  matchLabels:
                    app.kubernetes.io/component: distributor
                topologyKey: kubernetes.io/hostname
            - weight: 100
              podAffinityTerm:
                labelSelector:
                  matchLabels:
                    app.kubernetes.io/component: distributor
                topologyKey: topology.kubernetes.io/zone
    ingester:
      <<: *globalExtra
      replicas: 8
      persistence:
        enabled: true
        claims:
          - name: data
            size: 50Gi
            storageClass: yc-network-ssd
      autoscaling:
        enabled: false
      resources:
        requests:
          memory: "5Gi"
          cpu: "600m"
        limits:
          memory: "10Gi"
      maxUnavailable: 1
      zoneAwareReplication:
        zoneA:
          nodeSelector:
            topology.kubernetes.io/zone: ru-central1-a
            role: loki
        zoneB:
          nodeSelector:
            topology.kubernetes.io/zone: ru-central1-b
            role: loki
        zoneC:
          nodeSelector:
            topology.kubernetes.io/zone: ru-central1-d
            role: loki
    indexGateway:
      <<: *globalExtra
      replicas: 3
      enabled: true
      persistence:
        enabled: true
        storageClass: yc-network-ssd
      resources:
        requests:
          memory: "2Gi"
          cpu: "500m"
        limits:
          memory: "4Gi"
      maxUnavailable: 1
    querier:
      <<: *globalExtra
      autoscaling:
        enabled: true
        minReplicas: 7
        maxReplicas: 15
        targetCPUUtilizationPercentage: 70
        targetMemoryUtilizationPercentage: 70
      resources:
        requests:
          memory: "3Gi"
          cpu: "2500m"
        limits:
          memory: "5Gi"
      affinity:
        podAntiAffinity:
          requiredDuringSchedulingIgnoredDuringExecution: []
          preferredDuringSchedulingIgnoredDuringExecution:
            - weight: 99
              podAffinityTerm:
                labelSelector:
                  matchLabels:
                    app.kubernetes.io/component: querier
                topologyKey: kubernetes.io/hostname
            - weight: 100
              podAffinityTerm:
                labelSelector:
                  matchLabels:
                    app.kubernetes.io/component: querier
                topologyKey: topology.kubernetes.io/zone
      maxUnavailable: 1
    queryFrontend:
      <<: *globalExtra
      autoscaling:
        enabled: true
        minReplicas: 2
        maxReplicas: 4
        targetCPUUtilizationPercentage: 60
        targetMemoryUtilizationPercentage: 60
      resources:
        requests:
          memory: "1024Mi"
          cpu: "100m"
        limits:
          memory: "1024Mi"
      affinity:
        podAntiAffinity:
          requiredDuringSchedulingIgnoredDuringExecution: []
          preferredDuringSchedulingIgnoredDuringExecution:
            - weight: 99
              podAffinityTerm:
                labelSelector:
                  matchLabels:
                    app.kubernetes.io/component: query-frontend
                topologyKey: kubernetes.io/hostname
            - weight: 100
              podAffinityTerm:
                labelSelector:
                  matchLabels:
                    app.kubernetes.io/component: query-frontend
                topologyKey: topology.kubernetes.io/zone
      maxUnavailable: 1
    queryScheduler:
      <<: *globalExtra
      replicas: 1
    loki:
      auth_enabled: false
      storage:
        type: s3
        bucketNames:
          chunks: core-loki
          ruler: core-loki
          admin: core-loki
        s3:
          endpoint: https://storage.cloud.net:443/
          region: ru-central1
          bucketnames: core-loki
          secretAccessKey: "${S3_SECRET_ACCESS_KEY}"
          accessKeyId: "${S3_ACCESS_KEY_ID}"
        tsdb_shipper:
          shared_store: s3
          active_index_directory: /var/loki/tsdb-index
          cache_location: /var/loki/tsdb-cache
      schemaConfig:
        configs:
          - from: "2020-01-01"
            store: tsdb
            object_store: s3
            schema: v12
            index:
              prefix: tsdb_index_
              period: 24h
      distributor:
        ring:
          kvstore:
            store: memberlist
      ingester:
        lifecycler:
          ring:
            kvstore:
              store: memberlist
            replication_factor: 1
        autoforget_unhealthy: true
        chunk_idle_period: 1h
        chunk_target_size: 1572864
        max_chunk_age: 1h
        chunk_encoding: snappy
      server:
        grpc_server_max_recv_msg_size: 4194304
        grpc_server_max_send_msg_size: 4194304
      limits_config:
        allow_structured_metadata: false
        reject_old_samples: true
        reject_old_samples_max_age: 168h
        max_cache_freshness_per_query: 10m
        split_queries_by_interval: 15m
        retention_period: 30d
        max_global_streams_per_user: 0
        ingestion_rate_mb: 30
        query_timeout: 300s
        volume_enabled: true
      memcached:
        chunk_cache:
          enabled: true
        results_cache:
          enabled: true
      rulerConfig:
        remote_write:
          enabled: true
          clients:
            vmagent_local:
              url: http://vmagent-victoria-metrics-k8s-stack.victoria-metrics.svc:8429/api/v1/write?extra_label=cluster=infra
    ruler:
      enabled: true
      replicas: 1
      <<: *globalExtra
      extraArgs:
        - "-config.expand-env=true"
        # loki chart set {{- define "loki.rulerStorageConfig" -}} from global .Values.loki.storage.s3
        - "-ruler.storage.type=local"
        - "-ruler.storage.local.directory=/etc/loki/rules"
      storage:
        type: local
        local:
          directory: /etc/loki/rules
      persistence:
        enabled: true
        size: 10Gi
      ring:
        kvstore:
          store: memberlist
      directories:
        fake:
          rules.txt: |
            groups:
              - name: logs2metrics
                interval: 1m
                rules:
                - record: panic_count
                  expr: |
                    sum by (app,cluster) (
                      count_over_time({app=~".+",level!~"INFO|info|debug"}|="panic"[5m])
                    )
                - record: logs_size_by_app
                  expr:  |
                    sum by (app,cluster)(
                      bytes_over_time({app=~".+"}[1m])
                    )
    resultsCache:
      allocatedMemory: 4096
    chunksCache:
      allocatedMemory: 12288
    bloomCompactor:
      replicas: 0
    bloomGateway:
      replicas: 0
    backend:
      replicas: 0
    read:
      replicas: 0
    write:
      replicas: 0
    singleBinary:
      replicas: 0
    test:
      enabled: false
    lokiCanary:
      enabled: false
    monitoring:
      serviceMonitor:
        enabled: true
      rules:
        enabled: true

chunksCache:

chunk_store_config:
  chunk_cache_config:
    background:
      writeback_buffer: 500000
      writeback_goroutines: 1
      writeback_size_limit: 500MB
    default_validity: 0s
    memcached:
      batch_size: 4
      parallelism: 5
    memcached_client:
      addresses: dnssrvnoa+_memcached-client._tcp.loki-chunks-cache.loki-core.svc
      consistent_hash: true
      max_idle_conns: 72
      timeout: 2000ms

and resultsCache:

results_cache:
  cache:
    background:
      writeback_buffer: 500000
      writeback_goroutines: 1
      writeback_size_limit: 500MB
    default_validity: 12h
    memcached_client:
      addresses: dnssrvnoa+_memcached-client._tcp.loki-results-cache.loki-core.svc
      consistent_hash: true
      timeout: 500ms
      update_interval: 1m

Why chunksCache use memcached, but resultsCache use memcached_client?
Who writes in resultsCache?
How can I enable read-write logs in memcached?

[patsevanton]

memcached exist in chunk_store_config

memcached not exist in query_range

[earimont-ib]

@patsevanton Having same issue, thank you for opening this. Also nice dashboarding. Mind sharing where you got it from or the JSON? Thanks

[patsevanton]

@earimont-ib I think this dashboard is a simple memcached dashboard from the Internet.

[earimont-ib]

@patsevanton Found it, thank you.