iostat.tproj/iostat.8

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  32 .\"     @(#)iostat.8    8.1 (Berkeley) 6/6/93
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  34 .Dd June 6, 1993
  35 .Dt IOSTAT 8
  36 .Os BSD 4
  37 .Sh NAME
  38 .Nm iostat
  39 .Nd report
  40 .Tn I/O
  41 statistics
  42 .Sh SYNOPSIS
  43 .Nm iostat
  44 .Op Fl c Ar count
  45 .Op Fl M Ar core
  46 .Op Fl N Ar system
  47 .Op Fl w Ar wait
  48 .Op Ar drives
  49 .Sh DESCRIPTION
  50 .Nm Iostat
  51 displays kernel
  52 .Tn I/O
  53 statistics on terminal, disk and cpu
  54 operations.
  55 .Pp
  56 The options are as follows:
  57 .Bl -tag -width flag
  58 .It Fl c
  59 Repeat the display
  60 .Ar count
  61 times.
  62 The first display is for the time since a reboot and each subsequent
  63 report is for the time period since the last display.
  64 If no
  65 .Ar wait
  66 interval is specified, the default is 1 second.
  67 .It Fl M
  68 Extract values associated with the name list from the specified core
  69 instead of the default
  70 .Dq Pa /dev/kmem .
  71 .It Fl N
  72 Extract the name list from the specified system instead of the default
  73 .Dq Pa /vmunix .
  74 .It Fl w
  75 Pause
  76 .Ar wait
  77 seconds between each display.
  78 If no repeat
  79 .Ar count
  80 is specified, the default is infinity.
  81 .El
  82 .Pp
  83 .Nm Iostat
  84 displays its information in the following format:
  85 .Bl -tag -width flag
  86 .It tty
  87 .Bl -tag -width indent -compact
  88 .It tin
  89 characters read from terminals
  90 .It tout
  91 characters written to terminals
  92 .El
  93 .It disks
  94 Disk operations (this field is system dependent).
  95 The header of the field is the disk name and unit number.
  96 If more than four disk drives are configured in the system,
  97 .Nm iostat
  98 displays only the first four drives.
  99 To force
 100 .Nm iostat
 101 to display specific drives, their names may be supplied on the command
 102 line.
 103 .Pp
 104 .Bl -tag -width indent -compact
 105 .It sps
 106 sectors transferred per second
 107 .It tps
 108 transfers per second
 109 .It msps
 110 milliseconds per average seek (including implied
 111 seeks and rotational latency)
 112 .El
 113 .It cpu
 114 .Bl -tag -width indent -compact
 115 .It \&us
 116 % of cpu time in user mode
 117 .It \&ni
 118 % of cpu time in user mode running niced processes
 119 .It \&sy
 120 % of cpu time in system mode
 121 .It \&id
 122 % of cpu time in idle mode
 123 .El
 124 .El
 125 .Sh FILES
 126 .Bl -tag -width /dev/kmem -compact
 127 .It Pa /vmunix
 128 Default kernel namelist.
 129 .It Pa /dev/kmem
 130 Default memory file.
 131 .El
 132 .Sh SEE ALSO
 133 .Xr fstat 1 ,
 134 .Xr netstat 1 ,
 135 .Xr nfsstat 1 ,
 136 .Xr \&ps 1 ,
 137 .Xr systat 1 ,
 138 .Xr vmstat 1 ,
 139 .Xr pstat 8
 140 .Pp
 141 The sections starting with ``Interpreting system activity'' in
 142 .%T "Installing and Operating 4.3BSD" .