Promtail: handling tight loop in journal follow logic (#4066)

* Handling EBADMSG explicitly, and preventing tight loop Signed-off-by: Danny Kopping <danny.kopping@grafana.com> * Appeasing the linter Signed-off-by: Danny Kopping <danny.kopping@grafana.com>
grafana · Jul 28, 2021 · a3414a5 · a3414a5
1 parent 19aec6e
commit a3414a5
Showing 1 changed file with 8 additions and 2 deletions.
diff --git a/clients/pkg/promtail/targets/journal/journaltarget.go b/clients/pkg/promtail/targets/journal/journaltarget.go
@@ -7,6 +7,7 @@ import (
 	"io"
 	"io/ioutil"
 	"strings"
+	"syscall"
 	"time"
 
 	"github.com/coreos/go-systemd/sdjournal"
@@ -182,11 +183,16 @@ func journalTargetWithReader(
 		for {
 			err := t.r.Follow(until, ioutil.Discard)
 			if err != nil {
-				if err == sdjournal.ErrExpired || err == io.EOF {
+				level.Error(t.logger).Log("msg", "received error during sdjournal follow", "err", err.Error())
+
+				if err == sdjournal.ErrExpired || err == syscall.EBADMSG || err == io.EOF {
+					level.Error(t.logger).Log("msg", "unable to follow journal", "err", err.Error())
 					return
 				}
-				level.Error(t.logger).Log("msg", "received error during sdjournal follow", "err", err.Error())
 			}
+
+			// prevent tight loop
+			time.Sleep(100 * time.Millisecond)
 		}
 	}()