chore: optimize registry collector (#1683)

internal/perfdata/v1/collector.go

@@ -39,7 +39,7 @@ func (c *Collector) Describe() map[string]string {
 }
 
 func (c *Collector) Collect() (map[string]map[string]perftypes.CounterValues, error) {
- perfObjects, err := QueryPerformanceData(c.query)
+ perfObjects, err := QueryPerformanceData(c.query, c.object)
  if err != nil {
  return nil, fmt.Errorf("QueryPerformanceData: %w", err)
  }

internal/perfdata/v1/perflib.go

@@ -272,7 +272,7 @@ The query can be any of the following:
 Many objects have dependencies - if you query one of them, you often get back
 more than you asked for.
 */
-func QueryPerformanceData(query string) ([]*PerfObject, error) {
+func QueryPerformanceData(query string, counterName string) ([]*PerfObject, error) {
  buffer, err := queryRawData(query)
  if err != nil {
  return nil, err
@@ -297,6 +297,8 @@ func QueryPerformanceData(query string) ([]*PerfObject, error) {
  // Parse the performance data
 
  numObjects := int(header.NumObjectTypes)
+ numFilteredObjects := 0
+
  objects := make([]*PerfObject, numObjects)
 
  objOffset := int64(header.HeaderLength)
@@ -314,6 +316,14 @@ func QueryPerformanceData(query string) ([]*PerfObject, error) {
  return nil, err
  }
 
+ perfCounterName := obj.LookupName()
+
+ if counterName != "" && perfCounterName != counterName {
+ objOffset += int64(obj.TotalByteLength)
+
+ continue
+ }
+
  numCounterDefs := int(obj.NumCounters)
  numInstances := int(obj.NumInstances)
 
@@ -328,7 +338,7 @@ func QueryPerformanceData(query string) ([]*PerfObject, error) {
  counterDefs := make([]*PerfCounterDef, numCounterDefs)
 
  objects[i] = &PerfObject{
- Name: obj.LookupName(),
+ Name: perfCounterName,
  NameIndex: uint(obj.ObjectNameTitleIndex),
  Instances: instances,
  CounterDefs: counterDefs,
@@ -410,9 +420,10 @@ func QueryPerformanceData(query string) ([]*PerfObject, error) {
 
  // Next perfObjectType
  objOffset += int64(obj.TotalByteLength)
+ numFilteredObjects++
  }
 
- return objects, nil
+ return objects[:numFilteredObjects], nil
 }
 
 func parseCounterBlock(b []byte, r io.ReadSeeker, pos int64, defs []*PerfCounterDef) (int64, []*PerfCounter, error) {

internal/perfdata/v1/perflib_test.go

@@ -6,6 +6,6 @@ import (
 
 func BenchmarkQueryPerformanceData(b *testing.B) {
  for n := 0; n < b.N; n++ {
- _, _ = QueryPerformanceData("Global")
+ _, _ = QueryPerformanceData("Global", "")
  }
 }

internal/perfdata/v1/utils.go

@@ -9,7 +9,7 @@ func MapCounterToIndex(name string) string {
 }
 
 func GetPerflibSnapshot(objNames string) (map[string]*PerfObject, error) {
- objects, err := QueryPerformanceData(objNames)
+ objects, err := QueryPerformanceData(objNames, "")
  if err != nil {
  return nil, err
  }