tracker/stats/mem.go
2014-07-23 17:25:01 -04:00

83 lines
2.4 KiB
Go

// Copyright 2014 The Chihaya Authors. All rights reserved.
// Use of this source code is governed by the BSD 2-Clause license,
// which can be found in the LICENSE file.
package stats
import (
"encoding/json"
"runtime"
)
// BasicMemStats includes a few of the fields from runtime.MemStats suitable for
// general logging.
type BasicMemStats struct {
// General statistics.
Alloc uint64 // bytes allocated and still in use
TotalAlloc uint64 // bytes allocated (even if freed)
Sys uint64 // bytes obtained from system (sum of XxxSys below)
Lookups uint64 // number of pointer lookups
Mallocs uint64 // number of mallocs
Frees uint64 // number of frees
// Main allocation heap statistics.
HeapAlloc uint64 // bytes allocated and still in use
HeapSys uint64 // bytes obtained from system
HeapIdle uint64 // bytes in idle spans
HeapInuse uint64 // bytes in non-idle span
HeapReleased uint64 // bytes released to the OS
HeapObjects uint64 // total number of allocated objects
// Garbage collector statistics.
PauseTotalNs uint64
}
// MemStatsWrapper wraps runtime.MemStats with an optionally less verbose JSON
// representation. The JSON field names correspond exactly to the runtime field
// names to avoid reimplementing the entire struct.
type MemStatsWrapper struct {
basic *BasicMemStats
full *runtime.MemStats
verbose bool
}
func NewMemStatsWrapper(verbose bool) *MemStatsWrapper {
stats := &MemStatsWrapper{
verbose: verbose,
full: &runtime.MemStats{},
}
if !verbose {
stats.basic = &BasicMemStats{}
}
return stats
}
func (s *MemStatsWrapper) MarshalJSON() ([]byte, error) {
if s.verbose {
return json.Marshal(s.full)
} else {
return json.Marshal(s.basic)
}
}
// Update fetches the current memstats from runtime and resets the cache.
func (s *MemStatsWrapper) Update() {
runtime.ReadMemStats(s.full)
if !s.verbose {
// Gross, but any decent editor can generate this in a couple commands.
s.basic.Alloc = s.full.Alloc
s.basic.TotalAlloc = s.full.TotalAlloc
s.basic.Sys = s.full.Sys
s.basic.Lookups = s.full.Lookups
s.basic.Mallocs = s.full.Mallocs
s.basic.Frees = s.full.Frees
s.basic.HeapAlloc = s.full.HeapAlloc
s.basic.HeapSys = s.full.HeapSys
s.basic.HeapIdle = s.full.HeapIdle
s.basic.HeapInuse = s.full.HeapInuse
s.basic.HeapReleased = s.full.HeapReleased
s.basic.HeapObjects = s.full.HeapObjects
s.basic.PauseTotalNs = s.full.PauseTotalNs
}
}