Database statistics in Settings > Data

New GET /api/dbstats reads VictoriaLogs /metrics (stored lines, size on
disk, raw size, free space, partitions, retention) and two LogsQL queries
(period covered, distinct hosts and apps, lines of the last 24 h and hour),
cached for 30 s. The danger zone shows them, sizes in KB/MB/GB or Ko/Mo/Go.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

dbstats.go

@@ -0,0 +1,167 @@
+package main
+
+import (
+	"bufio"
+	"context"
+	"fmt"
+	"io"
+	"net/http"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+)
+
+// DBStats describes what VictoriaLogs holds (Settings > Data). Sizes are in
+// bytes; a field VictoriaLogs did not give stays at its zero value.
+type DBStats struct {
+	Rows       int64  `json:"rows"`       // stored log lines
+	DiskBytes  int64  `json:"diskBytes"`  // compressed data + index, on disk
+	IndexBytes int64  `json:"indexBytes"` // index part of DiskBytes
+	RawBytes   int64  `json:"rawBytes"`   // data before compression
+	FreeBytes  int64  `json:"freeBytes"`  // free space on the VictoriaLogs volume
+	Days       int64  `json:"days"`       // per-day partitions
+	Retention  string `json:"retention"`  // -retentionPeriod, e.g. "30d"
+	Oldest     string `json:"oldest,omitempty"`
+	Newest     string `json:"newest,omitempty"`
+	Last1h     int64  `json:"last1h"`
+	Last24h    int64  `json:"last24h"`
+	Hosts      int64  `json:"hosts"`
+	Apps       int64  `json:"apps"`
+	QueryError string `json:"queryError,omitempty"` // the LogsQL part failed, the metrics are still valid
+	Updated    string `json:"updated"`
+}
+
+// dbStatsCache keeps the last answer for a while: the LogsQL part reads the
+// whole base, which is too heavy to repeat each time the tab is opened.
+type dbStatsCache struct {
+	mu   sync.Mutex
+	at   time.Time
+	last *DBStats
+}
+
+const dbStatsTTL = 30 * time.Second
+
+func (c *dbStatsCache) get(ctx context.Context, s *Store, force bool) (*DBStats, error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if c.last != nil && !force && time.Since(c.at) < dbStatsTTL {
+		return c.last, nil
+	}
+	st, err := s.DBStats(ctx)
+	if err != nil {
+		return nil, err
+	}
+	c.last, c.at = st, time.Now()
+	return st, nil
+}
+
+// DBStats reads the storage metrics of VictoriaLogs (/metrics), then counts
+// with LogsQL what the metrics do not tell (period, recent volume, sources).
+func (s *Store) DBStats(ctx context.Context) (*DBStats, error) {
+	st, err := s.storageMetrics(ctx)
+	if err != nil {
+		return nil, err
+	}
+	st.Updated = time.Now().UTC().Format(time.RFC3339)
+	if st.Rows == 0 {
+		return st, nil
+	}
+
+	qctx, cancel := context.WithTimeout(ctx, 20*time.Second)
+	defer cancel()
+	rows, err := s.Query(qctx, "* | stats min(_time) oldest, max(_time) newest, count_uniq(host) hosts, count_uniq(app) apps")
+	if err == nil && len(rows) > 0 {
+		r := rows[0]
+		st.Oldest, _ = r["oldest"].(string)
+		st.Newest, _ = r["newest"].(string)
+		st.Hosts, st.Apps = toInt(r["hosts"]), toInt(r["apps"])
+		rows, err = s.Query(qctx, "_time:24h | stats count() last24h, count() if (_time:1h) last1h")
+		if err == nil && len(rows) > 0 {
+			st.Last24h, st.Last1h = toInt(rows[0]["last24h"]), toInt(rows[0]["last1h"])
+		}
+	}
+	if err != nil {
+		st.QueryError = err.Error()
+	}
+	return st, nil
+}
+
+func (s *Store) storageMetrics(ctx context.Context) (*DBStats, error) {
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, s.base+"/metrics", nil)
+	if err != nil {
+		return nil, err
+	}
+	resp, err := s.client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		msg, _ := io.ReadAll(io.LimitReader(resp.Body, 512))
+		return nil, fmt.Errorf("VictoriaLogs /metrics: HTTP %d: %s", resp.StatusCode, strings.TrimSpace(string(msg)))
+	}
+	return parseStorageMetrics(resp.Body)
+}
+
+// parseStorageMetrics picks the storage figures out of the Prometheus text
+// format of VictoriaLogs' /metrics (app/vlstorage).
+func parseStorageMetrics(r io.Reader) (*DBStats, error) {
+	st := &DBStats{}
+	sc := bufio.NewScanner(r)
+	sc.Buffer(make([]byte, 64*1024), 1<<20)
+	for sc.Scan() {
+		line := sc.Text()
+		if line == "" || line[0] == '#' {
+			continue
+		}
+		name, labels, value := splitMetric(line)
+		switch name {
+		case "vl_storage_rows":
+			st.Rows += int64(value)
+		case "vl_data_size_bytes":
+			st.DiskBytes += int64(value)
+			if labels["type"] == "indexdb" {
+				st.IndexBytes += int64(value)
+			}
+		case "vl_uncompressed_data_size_bytes":
+			st.RawBytes += int64(value)
+		case "vl_free_disk_space_bytes":
+			st.FreeBytes = int64(value)
+		case "vl_partitions":
+			st.Days = int64(value)
+		case "flag":
+			if labels["name"] == "retentionPeriod" {
+				st.Retention = labels["value"]
+			}
+		}
+	}
+	return st, sc.Err()
+}
+
+// splitMetric splits `name{a="x",b="y"} 12` into its parts. Label values with
+// escaped quotes are not expected in the metrics read here.
+func splitMetric(line string) (string, map[string]string, float64) {
+	sp := strings.LastIndexByte(line, ' ')
+	if sp < 0 {
+		return "", nil, 0
+	}
+	value, _ := strconv.ParseFloat(line[sp+1:], 64)
+	head := line[:sp]
+	name, rest, ok := strings.Cut(head, "{")
+	if !ok {
+		return head, nil, value
+	}
+	labels := map[string]string{}
+	rest = strings.TrimSuffix(rest, "}")
+	for rest != "" {
+		k, v, ok := strings.Cut(rest, `="`)
+		if !ok {
+			break
+		}
+		val, after, _ := strings.Cut(v, `"`)
+		labels[strings.TrimSpace(k)] = val
+		rest = strings.TrimPrefix(after, ",")
+	}
+	return name, labels, value
+}