vm-image-spec.yaml

# Supplemental file for neondatabase/autoscaling's vm-builder, for producing the VM compute image.
---
commands:
  - name: cgconfigparser
    user: root
    sysvInitAction: sysinit
    shell: 'cgconfigparser -l /etc/cgconfig.conf -s 1664'
  - name: pgbouncer
    user: postgres
    sysvInitAction: respawn
    shell: '/usr/local/bin/pgbouncer /etc/pgbouncer.ini'
  - name: postgres-exporter
    user: nobody
    sysvInitAction: respawn
    shell: 'DATA_SOURCE_NAME="user=cloud_admin sslmode=disable dbname=postgres" /bin/postgres_exporter'
  - name: sql-exporter
    user: nobody
    sysvInitAction: respawn
    shell: '/bin/sql_exporter -config.file=/etc/sql_exporter.yml'
shutdownHook: |
  su -p postgres --session-command '/usr/local/bin/pg_ctl stop -D /var/db/postgres/compute/pgdata -m fast --wait -t 10'
files:
  - filename: pgbouncer.ini
    content: |
      [databases]
      *=host=localhost port=5432 auth_user=cloud_admin
      [pgbouncer]
      listen_port=6432
      listen_addr=0.0.0.0
      auth_type=scram-sha-256
      auth_user=cloud_admin
      auth_dbname=postgres
      client_tls_sslmode=disable
      server_tls_sslmode=disable
      pool_mode=transaction
      max_client_conn=10000
      default_pool_size=64
      max_prepared_statements=0
      admin_users=postgres
      unix_socket_dir=/tmp/
      unix_socket_mode=0777
  - filename: cgconfig.conf
    content: |
      # Configuration for cgroups in VM compute nodes
      group neon-postgres {
          perm {
              admin {
                  uid = postgres;
              }
              task {
                  gid = users;
              }
          }
          memory {}
      }
  - filename: sql_exporter.yml
    content: |
      # Configuration for sql_exporter
      # Global defaults.
      global:
        # If scrape_timeout <= 0, no timeout is set unless Prometheus provides one. The default is 10s.
        scrape_timeout: 10s
        # Subtracted from Prometheus' scrape_timeout to give us some headroom and prevent Prometheus from timing out first.
        scrape_timeout_offset: 500ms
        # Minimum interval between collector runs: by default (0s) collectors are executed on every scrape.
        min_interval: 0s
        # Maximum number of open connections to any one target. Metric queries will run concurrently on multiple connections,
        # as will concurrent scrapes.
        max_connections: 1
        # Maximum number of idle connections to any one target. Unless you use very long collection intervals, this should
        # always be the same as max_connections.
        max_idle_connections: 1
        # Maximum number of maximum amount of time a connection may be reused. Expired connections may be closed lazily before reuse.
        # If 0, connections are not closed due to a connection's age.
        max_connection_lifetime: 5m

      # The target to monitor and the collectors to execute on it.
      target:
        # Data source name always has a URI schema that matches the driver name. In some cases (e.g. MySQL)
        # the schema gets dropped or replaced to match the driver expected DSN format.
        data_source_name: 'postgresql://cloud_admin@127.0.0.1:5432/postgres?sslmode=disable'

        # Collectors (referenced by name) to execute on the target.
        # Glob patterns are supported (see <https://pkg.go.dev/path/filepath#Match> for syntax).
        collectors: [neon_collector]

      # Collector files specifies a list of globs. One collector definition is read from each matching file.
      # Glob patterns are supported (see <https://pkg.go.dev/path/filepath#Match> for syntax).
      collector_files:
        - "neon_collector.yml"
  - filename: neon_collector.yml
    content: |
      collector_name: neon_collector
      metrics:
      - metric_name: lfc_misses
        type: gauge
        help: 'lfc_misses'
        key_labels:
        values: [lfc_misses]
        query: |
          select lfc_value as lfc_misses from neon.neon_lfc_stats where lfc_key='file_cache_misses';

      - metric_name: lfc_used
        type: gauge
        help: 'LFC chunks used (chunk = 1MB)'
        key_labels:
        values: [lfc_used]
        query: |
          select lfc_value as lfc_used from neon.neon_lfc_stats where lfc_key='file_cache_used';

      - metric_name: lfc_hits
        type: gauge
        help: 'lfc_hits'
        key_labels:
        values: [lfc_hits]
        query: |
          select lfc_value as lfc_hits from neon.neon_lfc_stats where lfc_key='file_cache_hits';

      - metric_name: lfc_writes
        type: gauge
        help: 'lfc_writes'
        key_labels:
        values: [lfc_writes]
        query: |
          select lfc_value as lfc_writes from neon.neon_lfc_stats where lfc_key='file_cache_writes';

      - metric_name: lfc_cache_size_limit
        type: gauge
        help: 'LFC cache size limit in bytes'
        key_labels:
        values: [lfc_cache_size_limit]
        query: |
          select pg_size_bytes(current_setting('neon.file_cache_size_limit')) as lfc_cache_size_limit;

      - metric_name: connection_counts
        type: gauge
        help: 'Connection counts'
        key_labels:
          - datname
          - state
        values: [count]
        query: |
          select datname, state, count(*) as count from pg_stat_activity where state <> '' group by datname, state;

      - metric_name: pg_stats_userdb
        type: gauge
        help: 'Stats for the oldest non-system db'
        key_labels:
          - datname
        value_label: kind
        values:
          - db_size
          - deadlocks
          # Rows
          - inserted
          - updated
          - deleted
        # We export stats for only one non-system database. Without this limit
        # it is too easy to abuse the system by creating lots of databases.
        # We can try lifting this limit in the future after we understand the needs better.
        query: |
          select pg_database_size(datname) as db_size, deadlocks,
                 tup_inserted as inserted, tup_updated as updated, tup_deleted as deleted,
                 datname
            from pg_stat_database
           where datname IN (
             select datname
               from pg_database
              where datname <> 'postgres' and not datistemplate
              order by oid
              limit 1
           );

      - metric_name: max_cluster_size
        type: gauge
        help: 'neon.max_cluster_size setting'
        key_labels:
        values: [max_cluster_size]
        query: |
          select setting::int as max_cluster_size from pg_settings where name = 'neon.max_cluster_size';

      - metric_name: db_total_size
        type: gauge
        help: 'Size of all databases'
        key_labels:
        values: [total]
        query: |
          select sum(pg_database_size(datname)) as total from pg_database;

      - metric_name: lfc_approximate_working_set_size
        type: gauge
        help: 'Approximate working set size in pages of 8192 bytes'
        key_labels:
        values: [approximate_working_set_size]
        query: |
          select neon.approximate_working_set_size(false) as approximate_working_set_size;

build: |
  # Build cgroup-tools
  #
  # At time of writing (2023-03-14), debian bullseye has a version of cgroup-tools (technically
  # libcgroup) that doesn't support cgroup v2 (version 0.41-11). Unfortunately, the vm-monitor
  # requires cgroup v2, so we'll build cgroup-tools ourselves.
  FROM debian:bullseye-slim as libcgroup-builder
  ENV LIBCGROUP_VERSION v2.0.3

  RUN set -exu \
      && apt update \
      && apt install --no-install-recommends -y \
          git \
          ca-certificates \
          automake \
          cmake \
          make \
          gcc \
          byacc \
          flex \
          libtool \
          libpam0g-dev \
      && git clone --depth 1 -b $LIBCGROUP_VERSION https://github.com/libcgroup/libcgroup \
      && INSTALL_DIR="/libcgroup-install" \
      && mkdir -p "$INSTALL_DIR/bin" "$INSTALL_DIR/include" \
      && cd libcgroup \
      # extracted from bootstrap.sh, with modified flags:
      && (test -d m4 || mkdir m4) \
      && autoreconf -fi \
      && rm -rf autom4te.cache \
      && CFLAGS="-O3" ./configure --prefix="$INSTALL_DIR" --sysconfdir=/etc --localstatedir=/var --enable-opaque-hierarchy="name=systemd" \
      # actually build the thing...
      && make install

  FROM quay.io/prometheuscommunity/postgres-exporter:v0.12.1 AS postgres-exporter

  FROM burningalchemist/sql_exporter:0.13 AS sql-exporter

  # Build pgbouncer
  #
  FROM debian:bullseye-slim AS pgbouncer
  RUN set -e \
      && apt-get update \
      && apt-get install -y \
          build-essential \
          git \
          libevent-dev \
          libtool \
          pkg-config

  # Use `dist_man_MANS=` to skip manpage generation (which requires python3/pandoc)
  ENV PGBOUNCER_TAG pgbouncer_1_22_1
  RUN set -e \
      && git clone --recurse-submodules --depth 1 --branch ${PGBOUNCER_TAG} https://github.com/pgbouncer/pgbouncer.git pgbouncer \
      && cd pgbouncer \
      && ./autogen.sh \
      && LDFLAGS=-static ./configure --prefix=/usr/local/pgbouncer --without-openssl \
      && make -j $(nproc) dist_man_MANS= \
      && make install dist_man_MANS=
merge: |
  # tweak nofile limits
  RUN set -e \
      && echo 'fs.file-max = 1048576' >>/etc/sysctl.conf \
      && test ! -e /etc/security || ( \
         echo '*    - nofile 1048576' >>/etc/security/limits.conf \
      && echo 'root - nofile 1048576' >>/etc/security/limits.conf \
         )

  COPY cgconfig.conf /etc/cgconfig.conf
  COPY pgbouncer.ini /etc/pgbouncer.ini
  COPY sql_exporter.yml /etc/sql_exporter.yml
  COPY neon_collector.yml /etc/neon_collector.yml

  RUN set -e \
      && chown postgres:postgres /etc/pgbouncer.ini \
      && chmod 0666 /etc/pgbouncer.ini \
      && chmod 0644 /etc/cgconfig.conf \
      && chmod 0644 /etc/sql_exporter.yml \
      && chmod 0644 /etc/neon_collector.yml

  COPY --from=libcgroup-builder /libcgroup-install/bin/*  /usr/bin/
  COPY --from=libcgroup-builder /libcgroup-install/lib/*  /usr/lib/
  COPY --from=libcgroup-builder /libcgroup-install/sbin/* /usr/sbin/
  COPY --from=postgres-exporter /bin/postgres_exporter /bin/postgres_exporter
  COPY --from=sql-exporter      /bin/sql_exporter      /bin/sql_exporter
  COPY --from=pgbouncer         /usr/local/pgbouncer/bin/pgbouncer /usr/local/bin/pgbouncer