Cluster:


apiVersion: postgresql.cnpg.io/v1
kind: Cluster
metadata:
  name: cluster-example
spec:
  instances: 3
  plugins:
  - name: cnpg-extensions.yandex.cloud      # Should always be "cnpg-extensions.yandex.cloud" for wal-g plugin
    isWALArchiver: true                     # Set to true to enable continuous WAL archiving
    parameters:
      backupConfig: example-backup-config   # Name of BackupConfig used to create backups
  postgresql:
    parameters:
      max_connections: "250"
      shared_buffers: 4GB
      effective_cache_size: 12GB
      maintenance_work_mem: 1GB
      checkpoint_completion_target: "0.9"
      wal_buffers: 16MB
      default_statistics_target: "100"
      random_page_cost: "1.1"
      effective_io_concurrency: "200"
      work_mem: 16513kB
      huge_pages: "off"
      min_wal_size: 1GB
      max_wal_size: 4GB
      max_worker_processes: "4"
      max_parallel_workers_per_gather: "2"
      max_parallel_workers: "4"
      max_parallel_maintenance_workers: "2"
    synchronous:
      method: any
      number: 1
      dataDurability: required
  storage:
    size: 1Gi


PGBench deployment:


apiVersion: apps/v1
kind: Deployment
metadata:
  name: pgbench-runner-cnpg
spec:
  replicas: 1
  selector:
    matchLabels:
      app: pgbench-runner-cnpg
  template:
    metadata:
      labels:
        app: pgbench-runner-cnpg
    spec:
      restartPolicy: Always  # important to avoid infinite restart of completed pods
      containers:
        - name: pgbench
          image: postgres:17
          resources:
            requests:
              cpu: "10m"
              memory: "128Mi"
            limits: {}
          env:
            - name: PGHOST
              valueFrom:
                secretKeyRef:
                  name: cluster-example-app
                  key: host
            - name: PGPORT
              valueFrom:
                secretKeyRef:
                  name: cluster-example-app
                  key: port
            - name: PGUSER
              valueFrom:
                secretKeyRef:
                  name: cluster-example-app
                  key: user
            - name: PGPASSWORD
              valueFrom:
                secretKeyRef:
                  name: cluster-example-app
                  key: password
            - name: PGDATABASE
              valueFrom:
                secretKeyRef:
                  name: cluster-example-app
                  key: dbname
          command: ["sh", "-c"]
          args:
            - |
              echo "Initializing benchmark database if needed...";
              pgbench -i -s 60 -d $PGDATABASE || true;
              echo "Running pgbench...";
              pgbench -j 6 -c 60 -b tpcb-like --time 600 -d $PGDATABASE

Postgres instance logs:


{"level":"info","ts":"2025-11-05T15:32:38.4179151Z","msg":"Starting up pg_rewind","logger":"instance-manager","logging_pod":"cluster-separate-wal-storage-1","controller":"instance-cluster","controllerGroup":"postgresql.cnpg.io","controllerKind":"Cluster","Cluster":{"name":"cluster-separate-wal-storage","namespace":"default"},"namespace":"default","name":"cluster-separate-wal-storage","reconcileID":"9063eeb8-8b27-45ec-a1cf-45305a5d63ff","logging_pod":"cluster-separate-wal-storage-1","pgdata":"/var/lib/postgresql/data/pgdata","options":["-P","--source-server","host=cluster-separate-wal-storage-rw user=streaming_replica port=5432 sslkey=/controller/certificates/streaming_replica.key sslcert=/controller/certificates/streaming_replica.crt sslrootcert=/controller/certificates/server-ca.crt application_name=cluster-separate-wal-storage-1 sslmode=verify-ca dbname=postgres","--target-pgdata","/var/lib/postgresql/data/pgdata","--restore-target-wal"]}

{"level":"info","ts":"2025-11-05T15:32:38.46084317Z","logger":"pg_rewind","msg":"pg_rewind: connected to server","pipe":"stderr","logging_pod":"cluster-separate-wal-storage-1"}

{"level":"info","ts":"2025-11-05T15:32:38.463751188Z","logger":"pg_rewind","msg":"pg_rewind: servers diverged at WAL location 1/7F1322D0 on timeline 1","pipe":"stderr","logging_pod":"cluster-separate-wal-storage-1"}

{"level":"info","ts":"2025-11-05T15:32:39.396083475Z","logger":"pg_rewind","msg":"pg_rewind: error: could not restore file \"00000001000000010000005F\" from archive","pipe":"stderr","logging_pod":"cluster-separate-wal-storage-1"}

{"level":"info","ts":"2025-11-05T15:32:39.396124895Z","logger":"pg_rewind","msg":"pg_rewind: error: could not find previous WAL record at 1/5FFFE728","pipe":"stderr","logging_pod":"cluster-separate-wal-storage-1"}

{"level":"error","ts":"2025-11-05T15:32:39.398028104Z","msg":"Failed to execute pg_rewind","logger":"instance-manager","logging_pod":"cluster-separate-wal-storage-1","controller":"instance-cluster","controllerGroup":"postgresql.cnpg.io","controllerKind":"Cluster","Cluster":{"name":"cluster-separate-wal-storage","namespace":"default"},"namespace":"default","name":"cluster-separate-wal-storage","reconcileID":"9063eeb8-8b27-45ec-a1cf-45305a5d63ff","logging_pod":"cluster-separate-wal-storage-1","options":["-P","--source-server","host=cluster-separate-wal-storage-rw user=streaming_replica port=5432 sslkey=/controller/certificates/streaming_replica.key sslcert=/controller/certificates/streaming_replica.crt sslrootcert=/controller/certificates/server-ca.crt application_name=cluster-separate-wal-storage-1 sslmode=verify-ca dbname=postgres","--target-pgdata","/var/lib/postgresql/data/pgdata","--restore-target-wal"],"error":"exit status 1","stacktrace":"github.com/cloudnative-pg/machinery/pkg/log.(*logger).Error\n\tpkg/mod/github.com/cloudnative-pg/machinery@v0.3.1/pkg/log/log.go:125\ngithub.com/cloudnative-pg/cloudnative-pg/pkg/management/postgres.(*Instance).Rewind\n\tpkg/management/postgres/instance.go:1165\ngithub.com/cloudnative-pg/cloudnative-pg/internal/management/controller.(*InstanceReconciler).verifyPgDataCoherenceForPrimary\n\tinternal/management/controller/instance_startup.go:140\ngithub.com/cloudnative-pg/cloudnative-pg/internal/management/controller.(*InstanceReconciler).initialize\n\tinternal/management/controller/instance_controller.go:457\ngithub.com/cloudnative-pg/cloudnative-pg/internal/management/controller.(*InstanceReconciler).Reconcile\n\tinternal/management/controller/instance_controller.go:193\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).Reconcile\n\tpkg/mod/sigs.k8s.io/controller-runtime@v0.21.0/pkg/internal/controller/controller.go:119\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).reconcileHandler\n\tpkg/mod/sigs.k8s.io/controller-runtime@v0.21.0/pkg/internal/controller/controller.go:340\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).processNextWorkItem\n\tpkg/mod/sigs.k8s.io/controller-runtime@v0.21.0/pkg/internal/controller/controller.go:300\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller...[]).Start.func2.1\n\tpkg/mod/sigs.k8s.io/controller-runtime@v0.21.0/pkg/internal/controller/controller.go:202"}



Plugin logs (using cnpg-plugin-wal-g):

{"level":"error","ts":"2025-11-05T15:32:39Z","logger":"plugin_wal","msg":"Failed to run wal-g fetch 00000001000000010000005F /var/lib/postgresql/data/pgdata/var/lib/postgresql/data/pgdata/pg_wal/00000001000000010000005F","method":"Restore","stdout":"","stderr":"ERROR: 2025/11/05 15:32:39.100804 open /var/lib/postgresql/data/pgdata/var/lib/postgresql/data/pgdata/pg_wal/00000001000000010000005F: no such file or directory\n","error":"subprocess run cmd result exit status 1"}