prometheus/postgres_exporter
1
0
Fork 0
mirror of https://github.com/prometheus-community/postgres_exporter.git synced 2025-10-31 09:10:25 +03:00
Code Activity

feat: allow setting limit in pg_stat_statements (#1205)

Browse Source 
Add `.limit` CLI flag to `stat_statements` collector to allow
setting a custom number of queries to be returned.

Signed-off-by: Cristian Greco <cristian@regolo.cc>
This commit is contained in:
Cristian Greco
2025-10-08 04:06:13 +02:00
committed by GitHub
parent a95b518a68
commit c70a059071
2 changed files with 216 additions and 25 deletions
Download Patch File Download Diff File Expand all files Collapse all files

33
collector/pg_stat_statements.go
View File

@@ -24,11 +24,15 @@ import (
"github.com/prometheus/client_golang/prometheus"
)
const statStatementsSubsystem = "stat_statements"
const (
statStatementsSubsystem = "stat_statements"
defaultStatementLimit = "100"
)
var (
includeQueryFlag *bool = nil
statementLengthFlag *uint = nil
statementLimitFlag *uint = nil
)
func init() {
@@ -47,12 +51,18 @@ func init() {
"Maximum length of the statement text.").
Default("120").
Uint()
statementLimitFlag = kingpin.Flag(
fmt.Sprint(collectorFlagPrefix, statStatementsSubsystem, ".limit"),
"Maximum number of statements to return.").
Default(defaultStatementLimit).
Uint()
}
type PGStatStatementsCollector struct {
log *slog.Logger
includeQueryStatement bool
statementLength uint
statementLimit uint
}
func NewPGStatStatementsCollector(config collectorConfig) (Collector, error) {
@@ -60,6 +70,7 @@ func NewPGStatStatementsCollector(config collectorConfig) (Collector, error) {
log: config.logger,
includeQueryStatement: *includeQueryFlag,
statementLength: *statementLengthFlag,
statementLimit: *statementLimitFlag,
}, nil
}
@@ -126,9 +137,9 @@ const (
FROM pg_stat_statements
)
ORDER BY seconds_total DESC
LIMIT 100;`
LIMIT %s;`
pgStatStatementsNewQuery = `SELECT
pgStatStatementsQuery_PG13 = `SELECT
pg_get_userbyid(userid) as user,
pg_database.datname,
pg_stat_statements.queryid,
@@ -148,7 +159,7 @@ const (
FROM pg_stat_statements
)
ORDER BY seconds_total DESC
LIMIT 100;`
LIMIT %s;`
pgStatStatementsQuery_PG17 = `SELECT
pg_get_userbyid(userid) as user,
@@ -170,7 +181,7 @@ const (
FROM pg_stat_statements
)
ORDER BY seconds_total DESC
LIMIT 100;`
LIMIT %s;`
)
func (c PGStatStatementsCollector) Update(ctx context.Context, instance *instance, ch chan<- prometheus.Metric) error {
@@ -179,20 +190,24 @@ func (c PGStatStatementsCollector) Update(ctx context.Context, instance *instanc
case instance.version.GE(semver.MustParse("17.0.0")):
queryTemplate = pgStatStatementsQuery_PG17
case instance.version.GE(semver.MustParse("13.0.0")):
queryTemplate = pgStatStatementsNewQuery
queryTemplate = pgStatStatementsQuery_PG13
default:
queryTemplate = pgStatStatementsQuery
}
var querySelect = ""
querySelect := ""
if c.includeQueryStatement {
querySelect = fmt.Sprintf(pgStatStatementQuerySelect, c.statementLength)
}
query := fmt.Sprintf(queryTemplate, querySelect)
statementLimit := defaultStatementLimit
if c.statementLimit > 0 {
statementLimit = fmt.Sprintf("%d", c.statementLimit)
}
query := fmt.Sprintf(queryTemplate, querySelect, statementLimit)
db := instance.getDB()
rows, err := db.QueryContext(ctx, query)
var presentQueryIds = make(map[string]struct{})
presentQueryIds := make(map[string]struct{})
if err != nil {
return err