@@ -10,24 +10,48 @@ import (
1010
1111"cdr.dev/slog"
1212"github.com/coder/coder/coderd/database"
13+ "github.com/coder/coder/coderd/database/dbauthz"
14+ "github.com/coder/coder/cryptorand"
1315)
1416
17+ const (
18+ jitter = 2 * time .Hour
19+ delay = 23 * time .Hour
20+ )
21+
22+ func nextTick () (time.Duration ,error ) {
23+ f ,err := cryptorand .Float64 ()
24+ if err != nil {
25+ return 0 ,err
26+ }
27+
28+ return delay + time .Duration (float64 (jitter )* f ),nil
29+ }
30+
1531// New creates a new periodically purging database instance.
1632// It is the caller's responsibility to call Close on the returned instance.
1733//
1834// This is for cleaning up old, unused resources from the database that take up space.
1935func New (ctx context.Context ,logger slog.Logger ,db database.Store ) io.Closer {
2036closed := make (chan struct {})
2137ctx ,cancelFunc := context .WithCancel (ctx )
38+ //nolint:gocritic // The system purges old db records without user input.
39+ ctx = dbauthz .AsSystemRestricted (ctx )
2240go func () {
2341defer close (closed )
24- ticker := time .NewTicker (24 * time .Hour )
25- defer ticker .Stop ()
42+ wait ,err := nextTick ()
43+ if err != nil {
44+ logger .Error (ctx ,"failed to generate random delay; exiting" ,slog .Error (err ))
45+ return
46+ }
47+
48+ timer := time .NewTimer (wait )
49+ defer timer .Stop ()
2650for {
2751select {
2852case <- ctx .Done ():
2953return
30- case <- ticker .C :
54+ case <- timer .C :
3155}
3256
3357var eg errgroup.Group
@@ -44,6 +68,13 @@ func New(ctx context.Context, logger slog.Logger, db database.Store) io.Closer {
4468}
4569logger .Error (ctx ,"failed to purge old database entries" ,slog .Error (err ))
4670}
71+
72+ wait ,err := nextTick ()
73+ if err != nil {
74+ logger .Error (ctx ,"failed to generate random delay; exiting" ,slog .Error (err ))
75+ return
76+ }
77+ timer .Reset (wait )
4778}
4879}()
4980return & instance {