diff --git a/collector/pg_stat_user_indexes.go b/collector/pg_stat_user_indexes.go new file mode 100644 index 000000000..e16a35e10 --- /dev/null +++ b/collector/pg_stat_user_indexes.go @@ -0,0 +1,141 @@ +// Copyright 2023 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +package collector + +import ( + "context" + "database/sql" + + "github.com/go-kit/log" + "github.com/go-kit/log/level" + "github.com/prometheus/client_golang/prometheus" +) + +func init() { + registerCollector(statUserIndexesSubsystem, defaultDisabled, NewPGStatUserIndexesCollector) +} + +type PGStatUserIndexesCollector struct { + log log.Logger +} + +const statUserIndexesSubsystem = "stat_user_indexes" + +func NewPGStatUserIndexesCollector(config collectorConfig) (Collector, error) { + return &PGStatUserIndexesCollector{log: config.logger}, nil +} + +var ( + statUserIndexesIdxScan = prometheus.NewDesc( + prometheus.BuildFQName(namespace, statUserIndexesSubsystem, "idx_scans_total"), + "Number of index scans initiated on this index", + []string{"schemaname", "relname", "indexrelname"}, + prometheus.Labels{}, + ) + statUserIndexesIdxTupRead = prometheus.NewDesc( + prometheus.BuildFQName(namespace, statUserIndexesSubsystem, "idx_tup_reads_total"), + "Number of index entries returned by scans on this index", + []string{"schemaname", "relname", "indexrelname"}, + prometheus.Labels{}, + ) + statUserIndexesIdxTupFetch = prometheus.NewDesc( + prometheus.BuildFQName(namespace, statUserIndexesSubsystem, "idx_tup_fetches_total"), + "Number of live table rows fetched by simple index scans using this index", + []string{"schemaname", "relname", "indexrelname"}, + prometheus.Labels{}, + ) + + statUserIndexesQuery = ` + SELECT + schemaname, + relname, + indexrelname, + idx_scan, + idx_tup_read, + idx_tup_fetch + FROM pg_stat_user_indexes + ` +) + +func (c *PGStatUserIndexesCollector) Update(ctx context.Context, instance *instance, ch chan<- prometheus.Metric) error { + db := instance.getDB() + rows, err := db.QueryContext(ctx, + statUserIndexesQuery) + + if err != nil { + return err + } + defer rows.Close() + for rows.Next() { + var schemaname, relname, indexrelname sql.NullString + var idxScan, idxTupRead, idxTupFetch sql.NullFloat64 + + if err := rows.Scan(&schemaname, &relname, &indexrelname, &idxScan, &idxTupRead, &idxTupFetch); err != nil { + return err + } + if !schemaname.Valid { + level.Debug(c.log).Log("msg", "Skipping stats on index because schemaname is not valid") + continue + } + if !relname.Valid { + level.Debug(c.log).Log("msg", "Skipping stats on index because relname is not valid") + continue + } + if !indexrelname.Valid { + level.Debug(c.log).Log("msg", "Skipping stats on index because indexrelname is not valid") + continue + } + labels := []string{schemaname.String, relname.String, indexrelname.String} + + if !idxScan.Valid { + level.Debug(c.log).Log("msg", "Skipping stats on index because idx_scan is not valid") + continue + } + if !idxTupRead.Valid { + level.Debug(c.log).Log("msg", "Skipping stats on index because idx_tup_read is not valid") + continue + } + if !idxTupFetch.Valid { + level.Debug(c.log).Log("msg", "Skipping stats on index because idx_tup_fetch is not valid") + continue + } + + idxScanMetric := idxScan.Float64 + ch <- prometheus.MustNewConstMetric( + statUserIndexesIdxScan, + prometheus.CounterValue, + idxScanMetric, + labels..., + ) + + idxTupReadMetric := idxTupRead.Float64 + ch <- prometheus.MustNewConstMetric( + statUserIndexesIdxTupRead, + prometheus.CounterValue, + idxTupReadMetric, + labels..., + ) + + idxTupFetchMetric := idxTupFetch.Float64 + ch <- prometheus.MustNewConstMetric( + statUserIndexesIdxTupFetch, + prometheus.CounterValue, + idxTupFetchMetric, + labels..., + ) + } + if err := rows.Err(); err != nil { + return err + } + return nil +} diff --git a/collector/pg_stat_user_indexes_test.go b/collector/pg_stat_user_indexes_test.go new file mode 100644 index 000000000..ce59355b7 --- /dev/null +++ b/collector/pg_stat_user_indexes_test.go @@ -0,0 +1,68 @@ +// Copyright 2023 The Prometheus Authors +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +package collector + +import ( + "context" + "testing" + + "github.com/DATA-DOG/go-sqlmock" + "github.com/prometheus/client_golang/prometheus" + dto "github.com/prometheus/client_model/go" + "github.com/smartystreets/goconvey/convey" +) + +func TestPgStatUserIndexesCollector(t *testing.T) { + db, mock, err := sqlmock.New() + if err != nil { + t.Fatalf("Error opening a stub db connection: %s", err) + } + defer db.Close() + inst := &instance{db: db} + columns := []string{ + "schemaname", + "relname", + "indexrelname", + "idx_scan", + "idx_tup_read", + "idx_tup_fetch", + } + rows := sqlmock.NewRows(columns). + AddRow("public", "pgbench_accounts", "pgbench_accounts_pkey", 5, 6, 7) + + mock.ExpectQuery(sanitizeQuery(statUserIndexesQuery)).WillReturnRows(rows) + + ch := make(chan prometheus.Metric) + go func() { + defer close(ch) + c := PGStatUserIndexesCollector{} + + if err := c.Update(context.Background(), inst, ch); err != nil { + t.Errorf("Error calling PGStatUserIndexesCollector.Update: %s", err) + } + }() + expected := []MetricResult{ + {labels: labelMap{"schemaname": "public", "relname": "pgbench_accounts", "indexrelname": "pgbench_accounts_pkey"}, value: 5, metricType: dto.MetricType_COUNTER}, + {labels: labelMap{"schemaname": "public", "relname": "pgbench_accounts", "indexrelname": "pgbench_accounts_pkey"}, value: 6, metricType: dto.MetricType_COUNTER}, + {labels: labelMap{"schemaname": "public", "relname": "pgbench_accounts", "indexrelname": "pgbench_accounts_pkey"}, value: 7, metricType: dto.MetricType_COUNTER}, + } + convey.Convey("Metrics comparison", t, func() { + for _, expect := range expected { + m := readMetric(<-ch) + convey.So(expect, convey.ShouldResemble, m) + } + }) + if err := mock.ExpectationsWereMet(); err != nil { + t.Errorf("there were unfulfilled exceptions: %s", err) + } +}