diff --git a/pkg/querier/tripperware/queryrange/limits_test.go b/pkg/querier/tripperware/queryrange/limits_test.go
index c1e5954421..d5d4a6b230 100644
--- a/pkg/querier/tripperware/queryrange/limits_test.go
+++ b/pkg/querier/tripperware/queryrange/limits_test.go
@@ -2,7 +2,6 @@ package queryrange
 
 import (
 	"context"
-	"github.com/cortexproject/cortex/pkg/util/validation"
 	"testing"
 	"time"
 
@@ -13,6 +12,7 @@ import (
 
 	"github.com/cortexproject/cortex/pkg/querier/tripperware"
 	"github.com/cortexproject/cortex/pkg/util"
+	"github.com/cortexproject/cortex/pkg/util/validation"
 )
 
 func TestLimitsMiddleware_MaxQueryLookback(t *testing.T) {
diff --git a/pkg/scheduler/queue/user_queues.go b/pkg/scheduler/queue/user_queues.go
index b0ae8069ac..25f562ee02 100644
--- a/pkg/scheduler/queue/user_queues.go
+++ b/pkg/scheduler/queue/user_queues.go
@@ -2,7 +2,6 @@ package queue
 
 import (
 	"math/rand"
-	"reflect"
 	"sort"
 	"time"
 
@@ -136,7 +135,7 @@ func (q *queues) getOrAddQueue(userID string, maxQueriers int) userRequestQueue
 	uq := q.userQueues[userID]
 	priorityEnabled := q.limits.QueryPriority(userID).Enabled
 	maxOutstanding := q.limits.MaxOutstandingPerTenant(userID)
-	priorityList := getPriorityList(q.limits.QueryPriority(userID), len(q.queriers))
+	priorityList := getPriorityList(q.limits.QueryPriority(userID), maxQueriers)
 
 	if uq == nil {
 		uq = &userQueue{
@@ -180,7 +179,7 @@ func (q *queues) getOrAddQueue(userID string, maxQueriers int) userRequestQueue
 		uq.queriers = shuffleQueriersForUser(uq.seed, maxQueriers, q.sortedQueriers, nil)
 	}
 
-	if priorityEnabled && !reflect.DeepEqual(uq.priorityList, priorityList) {
+	if priorityEnabled && hasPriorityListChanged(uq.priorityList, priorityList) {
 		reservedQueriers := make(map[string]int64)
 
 		i := 0
@@ -406,6 +405,18 @@ func getPriorityList(queryPriority validation.QueryPriority, totalQuerierCount i
 	return priorityList
 }
 
+func hasPriorityListChanged(old, new []int64) bool {
+	if len(old) != len(new) {
+		return true
+	}
+	for i := range old {
+		if old[i] != new[i] {
+			return true
+		}
+	}
+	return false
+}
+
 // MockLimits implements the Limits interface. Used in tests only.
 type MockLimits struct {
 	MaxOutstanding        int
diff --git a/pkg/scheduler/queue/user_queues_test.go b/pkg/scheduler/queue/user_queues_test.go
index ae812aac6a..ded597baa0 100644
--- a/pkg/scheduler/queue/user_queues_test.go
+++ b/pkg/scheduler/queue/user_queues_test.go
@@ -399,6 +399,7 @@ func TestGetOrAddQueueShouldUpdateProperties(t *testing.T) {
 	assert.Equal(t, 3, q.userQueues["userID"].maxQueriers)
 	assert.Equal(t, 5, len(q.queriers))
 	assert.Equal(t, 3, len(q.userQueues["userID"].queriers))
+	assert.Equal(t, 2, len(q.userQueues["userID"].reservedQueriers))
 	assert.IsType(t, &PriorityRequestQueue{}, queue)
 	assert.Equal(t, 1, queue.length())
 	assert.ElementsMatch(t, []int64{1, 1}, q.userQueues["userID"].priorityList)
@@ -406,6 +407,38 @@ func TestGetOrAddQueueShouldUpdateProperties(t *testing.T) {
 	assert.Subset(t, getKeys(q.queriers), getKeys(q.userQueues["userID"].queriers))
 	assert.Subset(t, getKeys(q.userQueues["userID"].queriers), getKeys(q.userQueues["userID"].reservedQueriers))
 
+	limits.QueryPriorityVal = validation.QueryPriority{Enabled: true, Priorities: []validation.PriorityDef{
+		{
+			Priority:         1,
+			ReservedQueriers: 0.5,
+		},
+	}}
+	q.limits = limits
+	_ = q.getOrAddQueue("userID", 3)
+
+	assert.Equal(t, 10, q.userQueues["userID"].maxOutstanding)
+	assert.Equal(t, 3, q.userQueues["userID"].maxQueriers)
+	assert.Equal(t, 5, len(q.queriers))
+	assert.Equal(t, 3, len(q.userQueues["userID"].queriers))
+	assert.Equal(t, 2, len(q.userQueues["userID"].reservedQueriers))
+	assert.ElementsMatch(t, []int64{1, 1}, q.userQueues["userID"].priorityList)
+
+	limits.QueryPriorityVal = validation.QueryPriority{Enabled: true, Priorities: []validation.PriorityDef{
+		{
+			Priority:         1,
+			ReservedQueriers: 10,
+		},
+	}}
+	q.limits = limits
+	_ = q.getOrAddQueue("userID", 3)
+
+	assert.Equal(t, 10, q.userQueues["userID"].maxOutstanding)
+	assert.Equal(t, 3, q.userQueues["userID"].maxQueriers)
+	assert.Equal(t, 5, len(q.queriers))
+	assert.Equal(t, 3, len(q.userQueues["userID"].queriers))
+	assert.Equal(t, 0, len(q.userQueues["userID"].reservedQueriers))
+	assert.ElementsMatch(t, []int64{}, q.userQueues["userID"].priorityList)
+
 	limits.QueryPriorityVal.Enabled = false
 	q.limits = limits
 	queue = q.getOrAddQueue("userID", 3)
@@ -582,69 +615,11 @@ func TestShuffleQueriersCorrectness(t *testing.T) {
 	}
 }
 
-func TestShuffleQueriers_WithReservedQueriers(t *testing.T) {
-	//allQueriers := []string{"a", "b", "c", "d", "e"}
-	//
-	//queriers, reservedQueriers := shuffleQueriersForUser(12345, 0, allQueriers, 0, nil)
-	//require.Nil(t, queriers)
-	//require.Equal(t, 0, len(reservedQueriers))
-	//
-	//queriers, reservedQueriers = shuffleQueriersForUser(12345, 0, allQueriers, 0.5, nil)
-	//require.Nil(t, queriers)
-	//require.Equal(t, 3, len(reservedQueriers))
-	//
-	//queriers, reservedQueriers = shuffleQueriersForUser(12345, 0, allQueriers, 1, nil)
-	//require.Nil(t, queriers)
-	//require.Equal(t, 1, len(reservedQueriers))
-	//
-	//queriers, reservedQueriers = shuffleQueriersForUser(12345, 0, allQueriers, 100, nil)
-	//require.Nil(t, queriers)
-	//require.Equal(t, 5, len(reservedQueriers))
-	//
-	//queriers, reservedQueriers = shuffleQueriersForUser(12345, 3, allQueriers, 0, nil)
-	//require.Equal(t, 3, len(queriers))
-	//require.Equal(t, 0, len(reservedQueriers))
-	//
-	//queriers, reservedQueriers = shuffleQueriersForUser(12345, 3, allQueriers, 0.5, nil)
-	//require.Equal(t, 3, len(queriers))
-	//require.Equal(t, 2, len(reservedQueriers))
-	//
-	//queriers, reservedQueriers = shuffleQueriersForUser(12345, 3, allQueriers, 1, nil)
-	//require.Equal(t, 3, len(queriers))
-	//require.Equal(t, 1, len(reservedQueriers))
-	//
-	//queriers, reservedQueriers = shuffleQueriersForUser(12345, 3, allQueriers, 100, nil)
-	//require.Equal(t, 3, len(queriers))
-	//require.Equal(t, 3, len(reservedQueriers))
-	//
-	//queriers, reservedQueriers = shuffleQueriersForUser(12345, 100, allQueriers, 0, nil)
-	//require.Nil(t, queriers)
-	//require.Equal(t, 0, len(reservedQueriers))
-	//
-	//queriers, reservedQueriers = shuffleQueriersForUser(12345, 100, allQueriers, 0.5, nil)
-	//require.Nil(t, queriers)
-	//require.Equal(t, 3, len(reservedQueriers))
-	//
-	//queriers, reservedQueriers = shuffleQueriersForUser(12345, 100, allQueriers, 1, nil)
-	//require.Nil(t, queriers)
-	//require.Equal(t, 1, len(reservedQueriers))
-	//
-	//queriers, reservedQueriers = shuffleQueriersForUser(12345, 100, allQueriers, 100, nil)
-	//require.Nil(t, queriers)
-	//require.Equal(t, 5, len(reservedQueriers))
-}
-
-func TestShuffleQueriers_WithReservedQueriers_Correctness(t *testing.T) {
-	//allQueriers := []string{"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n"}
-	//
-	//prevQueriers, prevReservedQueriers := shuffleQueriersForUser(12345, 10, allQueriers, 5, nil)
-	//for i := 0; i < 100; i++ {
-	//	queriers, reservedQueriers := shuffleQueriersForUser(12345, 10, allQueriers, 5, nil)
-	//	require.Equal(t, prevQueriers, queriers)
-	//	require.Equal(t, prevReservedQueriers, reservedQueriers)
-	//	prevQueriers = queriers
-	//	prevReservedQueriers = reservedQueriers
-	//}
+func TestHasPriorityListChanged(t *testing.T) {
+	require.True(t, hasPriorityListChanged([]int64{1, 2}, []int64{1, 3}))
+	require.False(t, hasPriorityListChanged([]int64{1, 2}, []int64{1, 2}))
+	require.True(t, hasPriorityListChanged([]int64{1, 2}, []int64{1}))
+	require.False(t, hasPriorityListChanged([]int64{}, []int64{}))
 }
 
 func TestGetPriorityList(t *testing.T) {