libgo/go/runtime/mem.go

   1 // Copyright 2009 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 package runtime
   6
   7 import "unsafe"
   8
   9 // Note: the MemStats struct should be kept in sync with
  10 // struct MStats in malloc.h
  11
  12 // A MemStats records statistics about the memory allocator.
  13 type MemStats struct {
  14         // General statistics.
  15         Alloc      uint64 // bytes allocated and still in use
  16         TotalAlloc uint64 // bytes allocated (even if freed)
  17         Sys        uint64 // bytes obtained from system (should be sum of XxxSys below)
  18         Lookups    uint64 // number of pointer lookups
  19         Mallocs    uint64 // number of mallocs
  20         Frees      uint64 // number of frees
  21
  22         // Main allocation heap statistics.
  23         HeapAlloc    uint64 // bytes allocated and still in use
  24         HeapSys      uint64 // bytes obtained from system
  25         HeapIdle     uint64 // bytes in idle spans
  26         HeapInuse    uint64 // bytes in non-idle span
  27         HeapReleased uint64 // bytes released to the OS
  28         HeapObjects  uint64 // total number of allocated objects
  29
  30         // Low-level fixed-size structure allocator statistics.
  31         //      Inuse is bytes used now.
  32         //      Sys is bytes obtained from system.
  33         StackInuse  uint64 // bootstrap stacks
  34         StackSys    uint64
  35         MSpanInuse  uint64 // mspan structures
  36         MSpanSys    uint64
  37         MCacheInuse uint64 // mcache structures
  38         MCacheSys   uint64
  39         BuckHashSys uint64 // profiling bucket hash table
  40
  41         // Garbage collector statistics.
  42         NextGC       uint64 // next run in HeapAlloc time (bytes)
  43         LastGC       uint64 // last run in absolute time (ns)
  44         PauseTotalNs uint64
  45         PauseNs      [256]uint64 // circular buffer of recent GC pause times, most recent at [(NumGC+255)%256]
  46         NumGC        uint32
  47         EnableGC     bool
  48         DebugGC      bool
  49
  50         // Per-size allocation statistics.
  51         // 61 is NumSizeClasses in the C code.
  52         BySize [61]struct {
  53                 Size    uint32
  54                 Mallocs uint64
  55                 Frees   uint64
  56         }
  57 }
  58
  59 var Sizeof_C_MStats uintptr // filled in by malloc.goc
  60
  61 var VmemStats MemStats
  62
  63 func init() {
  64         if Sizeof_C_MStats != unsafe.Sizeof(VmemStats) {
  65                 println(Sizeof_C_MStats, unsafe.Sizeof(VmemStats))
  66                 panic("MStats vs MemStatsType size mismatch")
  67         }
  68 }
  69
  70 // ReadMemStats populates m with memory allocator statistics.
  71 func ReadMemStats(m *MemStats)
  72
  73 // GC runs a garbage collection.
  74 func GC()