Record memory usage continuously in OOM report

experimental/libbox/internal/runtimeinfo/runtimeinfo.go

@@ -0,0 +1,74 @@
+package runtimeinfo
+
+import (
+	"encoding/json"
+	"os"
+	"runtime/metrics"
+)
+
+type Report struct {
+	Metrics    map[string]uint64 `json:"metrics"`
+	Goroutines *GoroutineReport  `json:"goroutines,omitempty"`
+	Pools      []PoolReport      `json:"bufferPools,omitempty"`
+}
+
+type GoroutineReport struct {
+	Total          int              `json:"total"`
+	StackBytes     uint64           `json:"stackBytes"`
+	Dead           int              `json:"dead"`
+	DeadStackBytes uint64           `json:"deadStackBytes"`
+	ByStatus       map[string]int   `json:"byStatus"`
+	ByFunction     []GoroutineGroup `json:"byFunction"`
+}
+
+type GoroutineGroup struct {
+	Function      string `json:"function"`
+	CreatedBy     string `json:"createdBy,omitempty"`
+	Count         int    `json:"count"`
+	StackBytes    uint64 `json:"stackBytes"`
+	MaxStackBytes uint64 `json:"maxStackBytes"`
+	MinStackBytes uint64 `json:"minStackBytes"`
+}
+
+type PoolReport struct {
+	Size   int    `json:"size"`
+	Cached int    `json:"cached"`
+	Victim int    `json:"victim"`
+	Bytes  uint64 `json:"bytes"`
+}
+
+func Collect() Report {
+	return Report{
+		Metrics:    collectMetrics(),
+		Goroutines: collectGoroutines(),
+		Pools:      collectBufferPools(),
+	}
+}
+
+func WriteFile(path string) error {
+	content, err := json.MarshalIndent(Collect(), "", "  ")
+	if err != nil {
+		return err
+	}
+	return os.WriteFile(path, content, 0o666)
+}
+
+func collectMetrics() map[string]uint64 {
+	descriptions := metrics.All()
+	samples := make([]metrics.Sample, 0, len(descriptions))
+	for _, description := range descriptions {
+		if description.Kind != metrics.KindUint64 {
+			continue
+		}
+		samples = append(samples, metrics.Sample{Name: description.Name})
+	}
+	metrics.Read(samples)
+	result := make(map[string]uint64, len(samples))
+	for _, sample := range samples {
+		if sample.Value.Kind() != metrics.KindUint64 {
+			continue
+		}
+		result[sample.Name] = sample.Value.Uint64()
+	}
+	return result
+}