kvclient: log internal rangefeed errors if no handler is present

stevendanna · stevendanna · commit c1b20fbadfff · 2025-10-27T18:30:37.000Z
Because of #75610, I find myself occasionally suspicious that some behavior is the result of a failed rangefeed client. This log line may help diagnose such issues. Informs #75610 Release note: None
diff --git a/pkg/kv/kvclient/rangefeed/rangefeed.go b/pkg/kv/kvclient/rangefeed/rangefeed.go
@@ -396,9 +396,10 @@ func (f *RangeFeed) run(ctx context.Context, frontier span.Frontier, resumeWithF
 			errors.HasType(err, &kvpb.MVCCHistoryMutationError{}) {
 			if errCallback := f.onUnrecoverableError; errCallback != nil {
 				errCallback(ctx, err)
+				log.VEventf(ctx, 1, "exiting rangefeed due to internal error: %v", err)
+			} else {
+				log.Dev.Warningf(ctx, "exiting rangefeed because of internal error with no OnInternalError callback: %s", err.Error())
 			}
-
-			log.VEventf(ctx, 1, "exiting rangefeed due to internal error: %v", err)
 			return
 		}
 		if err != nil && ctx.Err() == nil && restartLogEvery.ShouldLog() {

Original file line number	Diff line number	Diff line change
`@@ -396,9 +396,10 @@ func (f *RangeFeed) run(ctx context.Context, frontier span.Frontier, resumeWithF`
`396`	`396`	`errors.HasType(err, &kvpb.MVCCHistoryMutationError{}) {`
`397`	`397`	`if errCallback := f.onUnrecoverableError; errCallback != nil {`
`398`	`398`	`errCallback(ctx, err)`
	`399`	`+ log.VEventf(ctx, 1, "exiting rangefeed due to internal error: %v", err)`
	`400`	`+ } else {`
	`401`	`+ log.Dev.Warningf(ctx, "exiting rangefeed because of internal error with no OnInternalError callback: %s", err.Error())`
`399`	`402`	`}`
`400`		`-`
`401`		`- log.VEventf(ctx, 1, "exiting rangefeed due to internal error: %v", err)`
`402`	`403`	`return`
`403`	`404`	`}`
`404`	`405`	`if err != nil && ctx.Err() == nil && restartLogEvery.ShouldLog() {`