SYSTAT(1) | General Commands Manual | SYSTAT(1)

# NAME

`systat` — display system statistics

# SYNOPSIS

`systat` | [`-aBbhiNn`] [`-d` count] [`-s` delay] [`-w` width] [view] [delay]

# DESCRIPTION

`systat` displays various system statistics in a screen-oriented fashion using the curses(3) screen display library.

While `systat` is running, the screen is divided into different areas. The top line displays the current number of users, the three system load average figures over the last 1, 5, and 15 minute intervals, the host name, and the system time. The bottom line of the screen is reserved for user input and error messages. The information displayed in the rest of the screen comprises a view, and is the main interface for displaying different types of system statistics. The `vmstat` view is the default.

Certain information may be discarded when the screen size is insufficient for display. For example, on a machine with 10 drives the `iostat` bar graph displays only 3 drives on a 24 line terminal.

The options are as follows:

`-a`
  Display all lines.
`-B`
  Raw, non-interactive mode. The default is to exit after two screen updates, with statistics only ever displayed once. Useful for views such as `cpu`, where initial calculations are useless.
`-b`
  Raw, non-interactive mode. The default is to exit after one screen update, with statistics displayed every update.
`-d` count
  Exit after count screen updates.
`-h`
  Human readable mode, where applicable.
`-i`
  Interactive mode.
`-N`
  Resolve network addresses to names. This is the opposite of the `-n` option.
`-n`
  Do not try to reverse map IP addresses. This is the default.
`-s` delay
  Specifies the screen refresh time interval in seconds. This option is overridden by the final delay argument, if given. The default interval is 5 seconds.
`-w` width
  Specifies the maximum width of the output in raw, non-interactive mode.
view
  The view argument expects to be one of: `vmstat`, `pigs`, `ifstat`, `iostat`, `sensors`, `mbufs`, `netstat`, `swap`, `states`, `rules`, `queues`, `pf`, `pool`, `pcache`, `malloc`, `buckets`, `nfsclient`, `nfsserver`, `cpu`, or `uvm`. These displays can also be requested interactively and are described in full detail below. view may be abbreviated to the minimum unambiguous prefix; for example, “io” for “iostat”.
delay
  The delay argument specifies the screen refresh time interval in seconds. This is provided for backwards compatibility, and overrides any interval specified with the `-s` flag. The default interval is 5 seconds.

Certain characters cause immediate action by `systat`. These are:

`:`
  Move the cursor to the command line and interpret the input line typed as a command. While entering a command the current character erase, word erase, and line kill characters may be used.
`h`
  Toggle printing the names of the available views on the command line.
`o`
  Select the next ordering which sorts the rows according to a combination of columns. Available orderings depend on the view. Not all views support orderings.
`p`
  Pause `systat`.
`q`
  Quit `systat`.
`r`
  Reverse the selected ordering if supported by the view.
`s`
  Change the screen refresh interval in seconds.
`,`
  Print numbers with thousand separators, where applicable.
`^A` | ⟨`Home`⟩
  Jump to the beginning of the current view.
`^B` | ⟨`right arrow`⟩
  Select the previous view.
`^E` | ⟨`End`⟩
  Jump to the end of the current view.
`^F` | ⟨`left arrow`⟩
  Select the next view.
`^G`
  Toggle printing the name of the current view being shown and the refresh interval.
`^L`
  Refresh the screen.
`^N` | ⟨`down arrow`⟩
  Scroll current view down by one line.
`^P` | ⟨`up arrow`⟩
  Scroll current view up by one line.
`^V` | ⟨`Page Down`⟩
  Scroll current view down by one page.
`Alt-V` | ⟨`Page Up`⟩
  Scroll current view up by one page.

The following commands are interpreted by the “global” command interpreter.

`help`
  Toggle printing the names of the available views on the command line.
`human`
  Toggle human readable mode, where applicable.
`order`
  Toggle printing the names of the available orderings on the command line.
`quit`
  Quit `systat`. (This may be abbreviated to `q`.)
`stop`
  Stop refreshing the screen.
[`start`] [number]
  Start (continue) refreshing the screen. If a second, numeric, argument is provided it is interpreted as a refresh interval (in seconds). Supplying only a number will set the refresh interval to this value.

view may be abbreviated to the minimum unambiguous prefix. The available views are:

`buckets`
  Display kernel malloc(9) bucket statistics similar to the output of `vmstat` `-m`.
`cpu`
  Display information about the average usage of each CPU, similar to the output provided by top(1).
`ifstat`
  Display interface statistics. The “State” column has the format `up`|`dn`[:`U`|`D`]. ‘up’ and ‘dn’ represent whether the interface is up or down. ‘U’ and ‘D’ represent whether the interface is connected or not; in the case of carp(4) interfaces, whether the interface is in master or backup state, respectively.

  The character `B` changes the counter view between bytes and bits. Pressing `b` displays statistics as calculated from boot time. `r` changes the counters to show their totals as calculated between display refreshes. `t` changes the counters to show the average per second over the display refresh interval; this is the default. `d` displays input and output queue drops. `e` displays input and output errors. `f` displays input and output queue drops plus errors. This is the default view.

`iostat`
  Display statistics about disk throughput. Statistics on disk throughput show, for each drive, data transferred in bytes, number of disk transactions performed, and time spent in disk accesses (in fractions of a second). Pressing `b` displays statistics as calculated from boot time. `t` changes the counters to show the average per second over the display refresh interval; this is the default.
`malloc`
  Display kernel malloc(9) type statistics similar to the output of `vmstat` `-m`. Available orderings are: `name`, `inuse`, `memuse`, and `requests`.
`mbufs`
  Display mbuf usage information from kernel pools and mbuf cluster pool statistics of each network interface.
`netstat`
  Display network connections. Each address is displayed numerically in the format “host:port”. By default, network servers awaiting requests are not displayed. It is also possible to have addresses displayed symbolically, when possible, and limit the display to a set of protocols (the minimum unambiguous prefix may be supplied):
  `all`
    Toggle the displaying of server processes awaiting requests (this is the equivalent of the `-a` flag to netstat(1)).
  `names`
    Display network addresses symbolically.
  `numbers`
    Display network addresses numerically.
  `reset`
    Reset matching mechanisms to the default.
  `tcp` | `udp` | `other`
    Display only network connections using the indicated protocol.
`nfsclient`
  Display statistics about NFS client activity. Output resembles `nfsstat` `-c`.
`nfsserver`
  Display statistics about NFS server activity. Output resembles `nfsstat` `-s`.
`pf`
  Display filter information about pf(4), similar to the output of `pfctl` `-s` `info` option.
`pigs`
  Display those processes resident in main memory and getting the largest portion of the processor. When less than 100% of the processor is scheduled to user processes, the remaining time is accounted to the “idle” process.
`pool`
  Display kernel pool(9) statistics similar to the output of `vmstat` `-m`. Available orderings are: `name`, `requests`, `size`, and `number of pages`.

  By default only the statistics of active pools are displayed but pressing `A` changes the view to show all of them.

`pcache`
  Display kernel pool(9) per CPU cache statistics. Ordering is available on all columns.
`queues`
  Display statistics about the active queues, similar to the output of `pfctl` `-s` `queue`.
`rules`
  Display pf rules statistics, similar to the output of `pfctl` `-s` `rules`.
`sensors`
  Display the current values of available hardware sensors, in a format similar to that of sysctl(8).
`states`
  Display pf states statistics, similar to the output of `pfctl` `-s` `states`. Available orderings are: `none`, `bytes`, `expiry`, `packets`, `age`, `source address`, `source port`, `destination address`, `destination port`, `rate`, and `peak` columns.
`swap`
  Show information about swap space usage on all the swap areas compiled into the kernel. The first column is the device name of the partition. The next column is the total space available in the partition. The Used column indicates the total blocks used so far; the graph shows the percentage of space in use on each partition. If there is more than one swap partition in use, a total line is also shown. Areas known to the kernel but not in use are shown as not available.
`vmstat`
  Take over the entire display and show a (rather crowded) compendium of statistics related to virtual memory usage, process scheduling, device interrupts, system name translation caching, disk I/O, etc. This view is the default.

  Below the top line are statistics on memory utilization. The first row of the table reports memory usage only among active processes, that is, processes that have run in the previous twenty seconds. The second row reports on memory usage of all processes. The first column reports on the amount of physical memory claimed by processes. The second column reports the same figure for virtual memory, that is, the amount of memory that would be needed if all processes were resident at the same time. Finally, the last column shows the amount of physical memory on the free list.

  Below the memory display is a list of the average number of processes (over the last refresh interval) that are runnable (‘r’), in disk wait other than paging (‘d’), sleeping (‘s’), and swapped out but desiring to run (‘w’). Below the queue length listing is a numerical listing and a bar graph showing the amount of interrupt (shown as ‘`|`’), spinning (shown as ‘`@`’), system (shown as ‘`=`’), user plus nice (shown as ‘`>`’), and idle time (shown as ‘`` ’).

  To the right of the Proc display are statistics about Context switches (“Csw”), Traps (“Trp”), Syscalls (“Sys”), Interrupts (“Int”), Soft interrupts (“Sof”), and Faults (“Flt”) which have occurred during the last refresh interval.

  Below the CPU usage graph are statistics on name translations. It lists the number of names translated in the previous interval, the number and percentage of the translations that were handled by the system wide name translation cache, and the number and percentage of the translations that were handled by the per process name translation cache.

  At the bottom left is the disk usage display. It reports the number of seeks, transfers, number of kilobyte blocks transferred per second averaged over the refresh period of the display, and the time spent in disk accesses.

  Under the date in the upper right hand quadrant are statistics on paging and swapping activity. The first two columns report the average number of pages brought in and out per second over the last refresh interval due to page faults and the paging daemon. The third and fourth columns report the average number of pages brought in and out per second over the last refresh interval due to swap requests initiated by the scheduler. The first row of the display shows the average number of disk transfers per second over the last refresh interval. The second row of the display shows the average number of pages transferred per second over the last refresh interval.

  Running down the right hand side of the display is a breakdown of the interrupts being handled by the system. At the top of the list is the total interrupts per second over the time interval. The rest of the column breaks down the total on a device by device basis. Only devices that have interrupted at least once since boot time are shown.

  Below the Interrupts display are the average number of input and output packets per second for all interfaces over the last refresh interval.

  Below the SWAPPING display and slightly to the left of the Interrupts display is a list of virtual memory statistics. The abbreviations are:

  forks
    process forks
  fkppw
    forks where parent waits
  fksvm
    forks where vmspace is shared
  pwait
    fault had to wait on a page
  relck
    fault relock called
  rlkok
    fault relock is successful
  noram
    faults out of ram
  ndcpy
    number of times fault clears "need copy"
  fltcp
    number of times fault promotes with copy
  zfod
    fault promotes with zerofill
  cow
    number of times fault anon cow
  fmin
    min number of free pages
  ftarg
    target number of free pages
  itarg
    target number of inactive pages
  wired
    wired pages
  pdfre
    pages daemon freed since boot
  pdscn
    pages daemon scanned since boot
  pzidl
    number of zeroed pages
  kmape
    number of kernel map entries
`uvm`
  Display statistics relevant to the UVM subsystem. The statistics are divided into eight groups.

  Page Counters:
  npages
    pages managed by UVM
  free
    free pages
  active
    active pages
  inactive
    freed pages that may be wanted back
  paging
    pages in the process of being paged out
  wired
    wired pages
  zeropages
    zero'd pages
  reserve_pagedaemon
    pages reserved for pagedaemon
  reserve_kernel
    pages reserved for kernel.

  Stats Counters:
  faults
    page fault count
  traps
    trap count
  intrs
    interrupt count
  swtch
    context switch count
  softs
    software interrupt count
  syscalls
    system calls
  pageins
    pagein operation count
  pgswapin
    pages swapped in
  pgswapout
    pages swapped out
  forks
    forks.
  forks_ppwait
    forks where parent waits
  forks_sharevm
    forks where vmspace is shared
  pga_zerohit
    pagealloc found requested zero'd pages
  pga_zeromiss
    pagealloc failed to obtain zero'd pages

  Fault Counters:
  fltnoram
    fault was out of ram
  fltnoanon
    fault was out of anons
  fltnoamap
    fault was out of amap chunks
  fltpgwait
    fault had to wait on a page
  fltpgrele
    fault found a released page
  fltrelck
    fault relock was a success
  fltnorelck
    fault relock failed
  fltup
    fault upgrade was a success
  fltnoup
    fault upgrade failed
  fltanget
    fault got anon page
  fltanretry
    fault retried an anon get
  fltamcopy
    fault cleared "needs copy"
  fltnamap
    fault mapped a neighbor anon page
  fltnomap
    fault mapped a neighbor obj page
  fltlget
    fault did a locked pgo_get
  fltget
    fault did an unlocked get
  flt_anon
    fault anon (case 1a)
  flt_acow
    fault anon cow (case 1b)
  flt_obj
    fault was on object page (2a)
  flt_prcopy
    fault promotes with copy (2b)
  flt_przero
    fault promotes with zerofill (2b)

  Pageout Params:
  freemin
    minimum number of free pages
  freetarg
    target number of free pages
  inactarg
    target number of inactive pages
  wiredmax
    maximum number of wired pages

  Per-CPU Counters:
  pcphit
    pages allocated from a per-CPU cache since boot
  pcpmiss
    times a per-CPU cache was empty when allocating a page

  Swap Counters:
  nswapdev
    configured swap devices
  swpages
    PAGE_SIZE'ed swap pages
  swpginuse
    swap pages in use
  swpgonly
    in use swap pages not in RAM
  nswget
    swap pages moved from disk to RAM
  nanon
    total anon's

  Daemon Counters:
  pdwoke
    times daemon woke up
  pdrevs
    times daemon rev'd clock hand
  pdswout
    times daemon called for swapout
  pdfreed
    pages daemon freed since boot
  pdscans
    pages daemon scanned since boot
  pdanscan
    anonymous pages scanned by daemon
  pdobscan
    object pages scanned by daemon
  pdreact
    pages daemon reactivated since boot
  pdbusy
    times daemon found a busy page
  pdpageouts
    times daemon started a pageout
  pdpending
    times daemon got a pending pagout
  pddeact
    pages daemon deactivates

  Misc Counters:
  fpswtch
    FPU context switches
  kmapent
    kernel map entries

  Constants:
  pagesize
    size of a page, always a power of 2
  pagemask
    page mask
  pageshift
    page shift

# FILES

/etc/hosts
  Host names.
/etc/pf.conf
  pf(4) configuration.
/etc/services
  Port names.

# SEE ALSO

fstat(1), kill(1), netstat(1), nfsstat(1), ps(1), top(1), iostat(8), pfctl(8), pstat(8), renice(8), sysctl(8), vmstat(8)

# HISTORY

The `systat` program first appeared in 4.3BSD.

# BUGS

Certain displays presume a minimum of 80 characters per line. The `vmstat` display looks out of place because it is (it was added in as a separate display rather than created as a new program).

February 25, 2025 | Debian