chore: Memory align structs

pkg/metric_generator/generator.go:32:22: 16 bytes saved: struct with 96 pointer bytes could be 80
pkg/metrics_store/metrics_store.go:31:19: 40 bytes saved: struct with 64 pointer bytes could be 24
pkg/options/options.go:42:14: 24 bytes saved: struct of size 384 could be 360
internal/store/builder.go:67:14: 8 bytes saved: struct of size 200 could be 192
internal/store/pod.go:1351:16: 8 bytes saved: struct with 16 pointer bytes could be 8
internal/store/pod.go:1477:20: 8 bytes saved: struct with 16 pointer bytes could be 8
internal/store/testutils.go:32:30: 16 bytes saved: struct with 136 pointer bytes could be 120
pkg/metricshandler/metrics_handler.go:46:21: 8 bytes saved: struct of size 104 could be 96
internal/discovery/types.go:39:19: 32 bytes saved: struct with 88 pointer bytes could be 56
pkg/customresourcestate/config.go:51:15: 16 bytes saved: struct with 112 pointer bytes could be 96
pkg/customresourcestate/config.go:134:16: 8 bytes saved: struct with 88 pointer bytes could be 80
pkg/customresourcestate/config.go:150:13: 8 bytes saved: struct with 40 pointer bytes could be 32
pkg/customresourcestate/config_metrics_types.go:29:18: 8 bytes saved: struct with 64 pointer bytes could be 56
pkg/customresourcestate/config_metrics_types.go:42:17: 8 bytes saved: struct with 40 pointer bytes could be 32
pkg/customresourcestate/registry_factory.go:125:21: 8 bytes saved: struct with 40 pointer bytes could be 32
pkg/customresourcestate/registry_factory.go:212:20: 16 bytes saved: struct with 88 pointer bytes could be 72
pkg/customresourcestate/registry_factory.go:377:23: 8 bytes saved: struct with 104 pointer bytes could be 96
pkg/customresourcestate/registry_factory.go:497:21: 8 bytes saved: struct with 64 pointer bytes could be 56
pkg/customresourcestate/registry_factory.go:549:13: 8 bytes saved: struct with 24 pointer bytes could be 16

Author: mrueg

internal/discovery/types.go

@@ -37,18 +37,18 @@ type kindPlural struct {
 
 // CRDiscoverer provides a cache of the collected GVKs, along with helper utilities.
 type CRDiscoverer struct {
-	// m is a mutex to protect the cache.
-	m sync.RWMutex
-	// Map is a cache of the collected GVKs.
-	Map map[string]map[string][]kindPlural
-	// ShouldUpdate is a flag that indicates whether the cache was updated.
-	WasUpdated bool
 	// CRDsAddEventsCounter tracks the number of times that the CRD informer triggered the "add" event.
 	CRDsAddEventsCounter prometheus.Counter
 	// CRDsDeleteEventsCounter tracks the number of times that the CRD informer triggered the "remove" event.
 	CRDsDeleteEventsCounter prometheus.Counter
 	// CRDsCacheCountGauge tracks the net amount of CRDs affecting the cache at this point.
 	CRDsCacheCountGauge prometheus.Gauge
+	// Map is a cache of the collected GVKs.
+	Map map[string]map[string][]kindPlural
+	// m is a mutex to protect the cache.
+	m sync.RWMutex
+	// ShouldUpdate is a flag that indicates whether the cache was updated.
+	WasUpdated bool
 }
 
 // SafeRead executes the given function while holding a read lock.

internal/store/builder.go

@@ -65,24 +65,24 @@ var _ ksmtypes.BuilderInterface = &Builder{}
 // Builder helps to build store. It follows the builder pattern
 // (https://en.wikipedia.org/wiki/Builder_pattern).
 type Builder struct {
-	kubeClient            clientset.Interface
-	customResourceClients map[string]interface{}
-	namespaces            options.NamespaceList
-	// namespaceFilter is inside fieldSelectorFilter
-	fieldSelectorFilter           string
+	kubeClient                    clientset.Interface
 	ctx                           context.Context
-	enabledResources              []string
 	familyGeneratorFilter         generator.FamilyGeneratorFilter
+	customResourceClients         map[string]interface{}
 	listWatchMetrics              *watch.ListWatchMetrics
 	shardingMetrics               *sharding.Metrics
-	shard                         int32
-	totalShards                   int
 	buildStoresFunc               ksmtypes.BuildStoresFunc
 	buildCustomResourceStoresFunc ksmtypes.BuildCustomResourceStoresFunc
 	allowAnnotationsList          map[string][]string
 	allowLabelsList               map[string][]string
-	useAPIServerCache             bool
 	utilOptions                   *options.Options
+	// namespaceFilter is inside fieldSelectorFilter
+	fieldSelectorFilter string
+	namespaces          options.NamespaceList
+	enabledResources    []string
+	totalShards         int
+	shard               int32
+	useAPIServerCache   bool
 }
 
 // NewBuilder returns a new builder.

internal/store/pod.go

@@ -1349,14 +1349,14 @@ func createPodStatusPhaseFamilyGenerator() generator.FamilyGenerator {
 			}
 
 			phases := []struct {
-				v bool
 				n string
+				v bool
 			}{
-				{phase == v1.PodPending, string(v1.PodPending)},
-				{phase == v1.PodSucceeded, string(v1.PodSucceeded)},
-				{phase == v1.PodFailed, string(v1.PodFailed)},
-				{phase == v1.PodUnknown, string(v1.PodUnknown)},
-				{phase == v1.PodRunning, string(v1.PodRunning)},
+				{string(v1.PodPending), phase == v1.PodPending},
+				{string(v1.PodSucceeded), phase == v1.PodSucceeded},
+				{string(v1.PodFailed), phase == v1.PodFailed},
+				{string(v1.PodUnknown), phase == v1.PodUnknown},
+				{string(v1.PodRunning), phase == v1.PodRunning},
 			}
 
 			ms := make([]*metric.Metric, len(phases))
@@ -1475,12 +1475,12 @@ func createPodStatusQosClassFamilyGenerator() generator.FamilyGenerator {
 			}
 
 			qosClasses := []struct {
-				v bool
 				n string
+				v bool
 			}{
-				{class == v1.PodQOSBestEffort, string(v1.PodQOSBestEffort)},
-				{class == v1.PodQOSBurstable, string(v1.PodQOSBurstable)},
-				{class == v1.PodQOSGuaranteed, string(v1.PodQOSGuaranteed)},
+				{string(v1.PodQOSBestEffort), class == v1.PodQOSBestEffort},
+				{string(v1.PodQOSBurstable), class == v1.PodQOSBurstable},
+				{string(v1.PodQOSGuaranteed), class == v1.PodQOSGuaranteed},
 			}
 
 			ms := make([]*metric.Metric, len(qosClasses))

internal/store/testutils.go

@@ -31,12 +31,12 @@ import (
 
 type generateMetricsTestCase struct {
 	Obj                  interface{}
+	Func                 func(interface{}) []metric.FamilyInterface
+	Want                 string
 	MetricNames          []string
 	AllowAnnotationsList []string
 	AllowLabelsList      []string
-	Want                 string
 	Headers              []string
-	Func                 func(interface{}) []metric.FamilyInterface
 }
 
 func (testCase *generateMetricsTestCase) run() error {

pkg/customresourcestate/config.go

@@ -49,6 +49,10 @@ type MetricsSpec struct {
 
 // Resource configures a custom resource for metric generation.
 type Resource struct {
+
+	// Labels are added to all metrics. If the same key is used in a metric, the value from the metric will overwrite the value here.
+	Labels `yaml:",inline" json:",inline"`
+
 	// MetricNamePrefix defines a prefix for all metrics of the resource.
 	// If set to "", no prefix will be added.
 	// Example: If set to "foo", MetricNamePrefix will be "foo_<metric>".
@@ -57,16 +61,13 @@ type Resource struct {
 	// GroupVersionKind of the custom resource to be monitored.
 	GroupVersionKind GroupVersionKind `yaml:"groupVersionKind" json:"groupVersionKind"`
 
-	// Labels are added to all metrics. If the same key is used in a metric, the value from the metric will overwrite the value here.
-	Labels `yaml:",inline" json:",inline"`
+	// ResourcePlural sets the plural name of the resource. Defaults to the plural version of the Kind according to flect.Pluralize.
+	ResourcePlural string `yaml:"resourcePlural" json:"resourcePlural"`
 
 	// Metrics are the custom resource fields to be collected.
 	Metrics []Generator `yaml:"metrics" json:"metrics"`
 	// ErrorLogV defines the verbosity threshold for errors logged for this resource.
 	ErrorLogV klog.Level `yaml:"errorLogV" json:"errorLogV"`
-
-	// ResourcePlural sets the plural name of the resource. Defaults to the plural version of the Kind according to flect.Pluralize.
-	ResourcePlural string `yaml:"resourcePlural" json:"resourcePlural"`
 }
 
 // GetMetricNamePrefix returns the prefix to use for metrics.
@@ -132,25 +133,22 @@ func (l Labels) Merge(other Labels) Labels {
 
 // Generator describes a unique metric name.
 type Generator struct {
-	// Name of the metric. Subject to prefixing based on the configuration of the Resource.
-	Name string `yaml:"name" json:"name"`
-	// Help text for the metric.
-	Help string `yaml:"help" json:"help"`
 	// Each targets a value or values from the resource.
 	Each Metric `yaml:"each" json:"each"`
 
 	// Labels are added to all metrics. Labels from Each will overwrite these if using the same key.
 	Labels `yaml:",inline" json:",inline"` // json will inline because it is already tagged
+	// Name of the metric. Subject to prefixing based on the configuration of the Resource.
+	Name string `yaml:"name" json:"name"`
+	// Help text for the metric.
+	Help string `yaml:"help" json:"help"`
 	// ErrorLogV defines the verbosity threshold for errors logged for this metric. Must be non-zero to override the resource setting.
 	ErrorLogV klog.Level `yaml:"errorLogV" json:"errorLogV"`
 }
 
 // Metric defines a metric to expose.
 // +union
 type Metric struct {
-	// Type defines the type of the metric.
-	// +unionDiscriminator
-	Type metric.Type `yaml:"type" json:"type"`
 
 	// Gauge defines a gauge metric.
 	// +optional
@@ -161,6 +159,9 @@ type Metric struct {
 	// Info defines an info metric.
 	// +optional
 	Info *MetricInfo `yaml:"info" json:"info"`
+	// Type defines the type of the metric.
+	// +unionDiscriminator
+	Type metric.Type `yaml:"type" json:"type"`
 }
 
 // ConfigDecoder is for use with FromConfig.

pkg/customresourcestate/config_metrics_types.go

@@ -27,22 +27,22 @@ type MetricMeta struct {
 // MetricGauge targets a Path that may be a single value, array, or object. Arrays and objects will generate a metric per element.
 // Ref: https://github.com/OpenObservability/OpenMetrics/blob/main/specification/OpenMetrics.md#gauge
 type MetricGauge struct {
-	MetricMeta `yaml:",inline" json:",inline"`
+	// LabelFromKey adds a label with the given name if Path is an object. The label value will be the object key.
+	LabelFromKey string `yaml:"labelFromKey" json:"labelFromKey"`
+	MetricMeta   `yaml:",inline" json:",inline"`
 
 	// ValueFrom is the path to a numeric field under Path that will be the metric value.
 	ValueFrom []string `yaml:"valueFrom" json:"valueFrom"`
-	// LabelFromKey adds a label with the given name if Path is an object. The label value will be the object key.
-	LabelFromKey string `yaml:"labelFromKey" json:"labelFromKey"`
 	// NilIsZero indicates that if a value is nil it will be treated as zero value.
 	NilIsZero bool `yaml:"nilIsZero" json:"nilIsZero"`
 }
 
 // MetricInfo is a metric which is used to expose textual information.
 // Ref: https://github.com/OpenObservability/OpenMetrics/blob/main/specification/OpenMetrics.md#info
 type MetricInfo struct {
-	MetricMeta `yaml:",inline" json:",inline"`
 	// LabelFromKey adds a label with the given name if Path is an object. The label value will be the object key.
 	LabelFromKey string `yaml:"labelFromKey" json:"labelFromKey"`
+	MetricMeta   `yaml:",inline" json:",inline"`
 }
 
 // MetricStateSet is a metric which represent a series of related boolean values, also called a bitset.

pkg/customresourcestate/registry_factory.go

@@ -124,8 +124,8 @@ type compiledEach compiledMetric
 
 type compiledCommon struct {
 	labelFromPath map[string]valuePath
-	path          valuePath
 	t             metric.Type
+	path          valuePath
 }
 
 func (c compiledCommon) Path() valuePath {
@@ -211,9 +211,9 @@ func newCompiledMetric(m Metric) (compiledMetric, error) {
 
 type compiledGauge struct {
 	compiledCommon
+	labelFromKey string
 	ValueFrom    valuePath
 	NilIsZero    bool
-	labelFromKey string
 }
 
 func (c *compiledGauge) Values(v interface{}) (result []eachValue, errs []error) {
@@ -376,9 +376,9 @@ func (c *compiledInfo) values(v interface{}) (result []eachValue, err []error) {
 
 type compiledStateSet struct {
 	compiledCommon
+	LabelName string
 	ValueFrom valuePath
 	List      []string
-	LabelName string
 }
 
 func (c *compiledStateSet) Values(v interface{}) (result []eachValue, errs []error) {
@@ -495,11 +495,11 @@ func (e eachValue) ToMetric() *metric.Metric {
 }
 
 type compiledFamily struct {
-	Name          string
-	Help          string
 	Each          compiledEach
 	Labels        map[string]string
 	LabelFromPath map[string]valuePath
+	Name          string
+	Help          string
 	ErrorLogV     klog.Level
 }
 
@@ -547,8 +547,8 @@ func addPathLabels(obj interface{}, labels map[string]valuePath, result map[stri
 }
 
 type pathOp struct {
-	part string
 	op   func(interface{}) interface{}
+	part string
 }
 
 type valuePath []pathOp

pkg/metric_generator/generator.go

@@ -30,13 +30,13 @@ import (
 // DeprecatedVersion is defined only if the metric for which this options applies is,
 // in fact, deprecated.
 type FamilyGenerator struct {
+	GenerateFunc      func(obj interface{}) *metric.Family
 	Name              string
 	Help              string
 	Type              metric.Type
-	OptIn             bool
 	DeprecatedVersion string
 	StabilityLevel    basemetrics.StabilityLevel
-	GenerateFunc      func(obj interface{}) *metric.Family
+	OptIn             bool
 }
 
 // NewFamilyGeneratorWithStability creates new FamilyGenerator instances with metric

pkg/metrics_store/metrics_store.go

@@ -29,21 +29,22 @@ import (
 // interface. Instead of storing entire Kubernetes objects, it stores metrics
 // generated based on those objects.
 type MetricsStore struct {
-	// Protects metrics
-	mutex sync.RWMutex
 	// metrics is a map indexed by Kubernetes object id, containing a slice of
 	// metric families, containing a slice of metrics. We need to keep metrics
 	// grouped by metric families in order to zip families with their help text in
 	// MetricsStore.WriteAll().
 	metrics map[types.UID][][]byte
+
+	// generateMetricsFunc generates metrics based on a given Kubernetes object
+	// and returns them grouped by metric family.
+	generateMetricsFunc func(interface{}) []metric.FamilyInterface
 	// headers contains the header (TYPE and HELP) of each metric family. It is
 	// later on zipped with with their corresponding metric families in
 	// MetricStore.WriteAll().
 	headers []string
 
-	// generateMetricsFunc generates metrics based on a given Kubernetes object
-	// and returns them grouped by metric family.
-	generateMetricsFunc func(interface{}) []metric.FamilyInterface
+	// Protects metrics
+	mutex sync.RWMutex
 }
 
 // NewMetricsStore returns a new MetricsStore

pkg/metricshandler/metrics_handler.go

@@ -44,18 +44,18 @@ import (
 // MetricsHandler is a http.Handler that exposes the main kube-state-metrics
 // /metrics endpoint. It allows concurrent reconfiguration at runtime.
 type MetricsHandler struct {
-	opts               *options.Options
-	kubeClient         kubernetes.Interface
-	storeBuilder       ksmtypes.BuilderInterface
-	enableGZIPEncoding bool
+	kubeClient   kubernetes.Interface
+	storeBuilder ksmtypes.BuilderInterface
+	opts         *options.Options
 
 	cancel func()
 
 	// mtx protects metricsWriters, curShard, and curTotalShards
-	mtx            *sync.RWMutex
-	metricsWriters metricsstore.MetricsWriterList
-	curShard       int32
-	curTotalShards int
+	mtx                *sync.RWMutex
+	metricsWriters     metricsstore.MetricsWriterList
+	curTotalShards     int
+	curShard           int32
+	enableGZIPEncoding bool
 }
 
 // New creates and returns a new MetricsHandler with the given options.