Merge #90448 #91146

90448: admission: Disable admission control for user requests r=andrewbaptist a=andrewbaptist informs: #85641 Only leave admission control in place for elastic / bulk requests. Release note: None 91146: storage: enable MVCC range tombstones by default r=erikgrinaker a=erikgrinaker Resolves #88708. Release note: None Co-authored-by: Andrew Baptist <[email protected]> Co-authored-by: Erik Grinaker <[email protected]>
cockroachdb · Nov 3, 2022 · 0965142 · 0965142
3 parents 42c6d47 + c8c8535 + 3d34800
commit 0965142
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Showing 3 changed files with 23 additions and 3 deletions.
diff --git a/pkg/kv/kvserver/store.go b/pkg/kv/kvserver/store.go
@@ -4024,6 +4024,13 @@ func (n *KVAdmissionControllerImpl) AdmitKVWork(
 	if source == roachpb.AdmissionHeader_OTHER {
 		bypassAdmission = true
 	}
+	// TODO(abaptist): Revisit and deprecate this setting in v23.1.
+	if admission.KVBulkOnlyAdmissionControlEnabled.Get(&n.settings.SV) {
+		if admissionpb.WorkPriority(ba.AdmissionHeader.Priority) >= admissionpb.NormalPri {
+			bypassAdmission = true
+		}
+	}
+
 	createTime := ba.AdmissionHeader.CreateTime
 	if !bypassAdmission && createTime == 0 {
 		// TODO(sumeer): revisit this for multi-tenant. Specifically, the SQL use

diff --git a/pkg/storage/mvcc.go b/pkg/storage/mvcc.go
@@ -83,9 +83,8 @@ var minWALSyncInterval = settings.RegisterDurationSetting(
 var MVCCRangeTombstonesEnabled = settings.RegisterBoolSetting(
 	settings.SystemOnly,
 	"storage.mvcc.range_tombstones.enabled",
-	"experimental: if true, enable the use of MVCC range tombstones. Do not enable "+
-		"unless you're aware of the corruption risk.",
-	false)
+	"enables the use of MVCC range tombstones",
+	true)
 
 // CanUseMVCCRangeTombstones returns true if the caller can begin writing
 // MVCC range tombstones, by setting DeleteRangeRequest.UseRangeTombstone.

diff --git a/pkg/util/admission/work_queue.go b/pkg/util/admission/work_queue.go
@@ -51,6 +51,20 @@ var KVAdmissionControlEnabled = settings.RegisterBoolSetting(
 	"when true, work performed by the KV layer is subject to admission control",
 	true).WithPublic()
 
+// KVBulkOnlyAdmissionControlEnabled controls whether user (normal and above
+// priority) work is subject to admission control. If it is set to true, then
+// user work will not be throttled by admission control but bulk work still will
+// be. This setting is a preferable alternative to completely disabling
+// admission control. It can be used reactively in cases where index backfill,
+// schema modifications or other bulk operations are causing high latency due to
+// io_overload on nodes.
+// TODO(baptist): Find a better solution to this in v23.1.
+var KVBulkOnlyAdmissionControlEnabled = settings.RegisterBoolSetting(
+	settings.SystemOnly,
+	"admission.kv.bulk_only.enabled",
+	"when both admission.kv.enabled and this is true, only throttle bulk work",
+	false)
+
 // SQLKVResponseAdmissionControlEnabled controls whether response processing
 // in SQL, for KV requests, is enabled.
 var SQLKVResponseAdmissionControlEnabled = settings.RegisterBoolSetting(