From 92de6ea3407ad35ad816baf9278ae9dc470a3d63 Mon Sep 17 00:00:00 2001
From: Aliaksandr Valialkin <valyala@victoriametrics.com>
Date: Sun, 12 May 2024 10:20:39 +0200
Subject: [PATCH] app/vmselect: use strings.EqualFold instead of
 strings.ToLower where appropriate

Strings.EqualFold doesn't allocate memory contrary to strings.ToLower if the input string contains uppercase chars
---
 app/vmselect/graphiteql/parser.go |  4 ++--
 app/vmselect/promql/binary_op.go  |  4 ++--
 app/vmselect/promql/eval.go       | 10 +++++-----
 app/vmselect/promql/exec.go       |  2 +-
 4 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/app/vmselect/graphiteql/parser.go b/app/vmselect/graphiteql/parser.go
index b827c0f0e1..a56bf74e65 100644
--- a/app/vmselect/graphiteql/parser.go
+++ b/app/vmselect/graphiteql/parser.go
@@ -213,11 +213,11 @@ func (p *parser) parseMetricExprOrFuncCall() (Expr, error) {
 		// Metric epxression or bool expression or None.
 		if isBool(ident) {
 			be := &BoolExpr{
-				B: strings.ToLower(ident) == "true",
+				B: strings.EqualFold(ident, "true"),
 			}
 			return be, nil
 		}
-		if strings.ToLower(ident) == "none" {
+		if strings.EqualFold(ident, "none") {
 			nne := &NoneExpr{}
 			return nne, nil
 		}
diff --git a/app/vmselect/promql/binary_op.go b/app/vmselect/promql/binary_op.go
index 0cf2f75280..ac347e5048 100644
--- a/app/vmselect/promql/binary_op.go
+++ b/app/vmselect/promql/binary_op.go
@@ -112,7 +112,7 @@ func binaryOpNeqFunc(bfa *binaryOpFuncArg) ([]*timeseries, error) {
 }
 
 func isUnionFunc(e metricsql.Expr) bool {
-	if fe, ok := e.(*metricsql.FuncExpr); ok && (fe.Name == "" || strings.ToLower(fe.Name) == "union") {
+	if fe, ok := e.(*metricsql.FuncExpr); ok && (fe.Name == "" || strings.EqualFold(fe.Name, "union")) {
 		return true
 	}
 	return false
@@ -303,7 +303,7 @@ func ensureSingleTimeseries(side string, be *metricsql.BinaryOpExpr, tss []*time
 func groupJoin(singleTimeseriesSide string, be *metricsql.BinaryOpExpr, rvsLeft, rvsRight, tssLeft, tssRight []*timeseries) ([]*timeseries, []*timeseries, error) {
 	joinTags := be.JoinModifier.Args
 	var skipTags []string
-	if strings.ToLower(be.GroupModifier.Op) == "on" {
+	if strings.EqualFold(be.GroupModifier.Op, "on") {
 		skipTags = be.GroupModifier.Args
 	}
 	joinPrefix := ""
diff --git a/app/vmselect/promql/eval.go b/app/vmselect/promql/eval.go
index 6113254731..2f8b32cdac 100644
--- a/app/vmselect/promql/eval.go
+++ b/app/vmselect/promql/eval.go
@@ -542,7 +542,7 @@ func execBinaryOpArgs(qt *querytracer.Tracer, ec *EvalConfig, exprFirst, exprSec
 	if err != nil {
 		return nil, nil, err
 	}
-	if len(tssFirst) == 0 && strings.ToLower(be.Op) != "or" {
+	if len(tssFirst) == 0 && !strings.EqualFold(be.Op, "or") {
 		// Fast path: there is no sense in executing the exprSecond when exprFirst returns an empty result,
 		// since the "exprFirst op exprSecond" would return an empty result in any case.
 		// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3349
@@ -1168,7 +1168,7 @@ func evalInstantRollup(qt *querytracer.Tracer, ec *EvalConfig, funcName string,
 		return evalExpr(qt, ec, be)
 	case "rate":
 		if iafc != nil {
-			if strings.ToLower(iafc.ae.Name) != "sum" {
+			if !strings.EqualFold(iafc.ae.Name, "sum") {
 				qt.Printf("do not apply instant rollup optimization for incremental aggregate %s()", iafc.ae.Name)
 				return evalAt(qt, timestamp, window)
 			}
@@ -1214,7 +1214,7 @@ func evalInstantRollup(qt *querytracer.Tracer, ec *EvalConfig, funcName string,
 		return evalExpr(qt, ec, be)
 	case "max_over_time":
 		if iafc != nil {
-			if strings.ToLower(iafc.ae.Name) != "max" {
+			if !strings.EqualFold(iafc.ae.Name, "max") {
 				qt.Printf("do not apply instant rollup optimization for non-max incremental aggregate %s()", iafc.ae.Name)
 				return evalAt(qt, timestamp, window)
 			}
@@ -1276,7 +1276,7 @@ func evalInstantRollup(qt *querytracer.Tracer, ec *EvalConfig, funcName string,
 		return tss, nil
 	case "min_over_time":
 		if iafc != nil {
-			if strings.ToLower(iafc.ae.Name) != "min" {
+			if !strings.EqualFold(iafc.ae.Name, "min") {
 				qt.Printf("do not apply instant rollup optimization for non-min incremental aggregate %s()", iafc.ae.Name)
 				return evalAt(qt, timestamp, window)
 			}
@@ -1345,7 +1345,7 @@ func evalInstantRollup(qt *querytracer.Tracer, ec *EvalConfig, funcName string,
 		"increase",
 		"increase_pure",
 		"sum_over_time":
-		if iafc != nil && strings.ToLower(iafc.ae.Name) != "sum" {
+		if iafc != nil && !strings.EqualFold(iafc.ae.Name, "sum") {
 			qt.Printf("do not apply instant rollup optimization for non-sum incremental aggregate %s()", iafc.ae.Name)
 			return evalAt(qt, timestamp, window)
 		}
diff --git a/app/vmselect/promql/exec.go b/app/vmselect/promql/exec.go
index 5414387ab5..c38de1293c 100644
--- a/app/vmselect/promql/exec.go
+++ b/app/vmselect/promql/exec.go
@@ -139,7 +139,7 @@ func maySortResults(e metricsql.Expr) bool {
 			return false
 		}
 	case *metricsql.BinaryOpExpr:
-		if strings.ToLower(v.Op) == "or" {
+		if strings.EqualFold(v.Op, "or") {
 			// Do not sort results for `a or b` in the same way as Prometheus does.
 			// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4763
 			return false