freebsd-nq/usr.bin/procstat/procstat.1
Ed Schouten bc093719ca Integrate the new MPSAFE TTY layer to the FreeBSD operating system.
The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:

- Improved driver model:

  The old TTY layer has a driver model that is not abstract enough to
  make it friendly to use. A good example is the output path, where the
  device drivers directly access the output buffers. This means that an
  in-kernel PPP implementation must always convert network buffers into
  TTY buffers.

  If a PPP implementation would be built on top of the new TTY layer
  (still needs a hooks layer, though), it would allow the PPP
  implementation to directly hand the data to the TTY driver.

- Improved hotplugging:

  With the old TTY layer, it isn't entirely safe to destroy TTY's from
  the system. This implementation has a two-step destructing design,
  where the driver first abandons the TTY. After all threads have left
  the TTY, the TTY layer calls a routine in the driver, which can be
  used to free resources (unit numbers, etc).

  The pts(4) driver also implements this feature, which means
  posix_openpt() will now return PTY's that are created on the fly.

- Improved performance:

  One of the major improvements is the per-TTY mutex, which is expected
  to improve scalability when compared to the old Giant locking.
  Another change is the unbuffered copying to userspace, which is both
  used on TTY device nodes and PTY masters.

Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.

Obtained from:		//depot/projects/mpsafetty/...
Approved by:		philip (ex-mentor)
Discussed:		on the lists, at BSDCan, at the DevSummit
Sponsored by:		Snow B.V., the Netherlands
dcons(4) fixed by:	kan
2008-08-20 08:31:58 +00:00

362 lines
7.2 KiB
Groff

.\"-
.\" Copyright (c) 2007-2008 Robert N. M. Watson
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.\" $FreeBSD$
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.Dd August 20, 2008
.Dt PROCSTAT 1
.Os
.Sh NAME
.Nm procstat
.Nd get detailed process information
.Sh SYNOPSIS
.Nm
.Op Fl h
.Op Fl w Ar interval
.Op Fl b | c | f | k | s | t | v
.Op Fl a | Ar pid ...
.Sh DESCRIPTION
The
.Nm
utility displays detailed information about the processes identified by the
.Ar pid
arguments, or if the
.Fl a
flag is used, all processes.
.Pp
By default, basic process statistics are printed; one of the following
options may be specified in order to select more detailed process information
for printing:
.Bl -tag -width indent
.It Fl b
Display binary information for the process.
.It Fl c
Display command line arguments for the process.
.It Fl f
Display file descriptor information for the process.
.It Fl k
Display the stacks of kernel threads in the process, excluding stacks of
threads currently running on a CPU and threads with stacks swapped to disk.
If the flag is repeated, function offsets as well as function names are
printed.
.It Fl s
Display security credential information for the process.
.It Fl t
Display thread information for the process.
.It Fl v
Display virtual memory mappings for the process.
.El
.Pp
All options generate output in the format of a table, the first field of
which is the process ID to which the row of information corresponds.
The
.Fl h
flag may be used to suppress table headers.
.Pp
The
.Fl w
flag may be used to specify a wait interval at which to repeat the printing
of the requested process information.
If the
.Fl w
flag is not specified, the output will not repeat.
.Pp
Some information, such as VM and file descriptor information, is available
only to the owner of a process or the superuser.
.Ss Binary Information
Display the process ID, command, and path to the process binary:
.Pp
.Bl -tag -width indent -compact
.It PID
process ID
.It COMM
command
.It PATH
path to process binary (if available)
.El
.Ss Command Line Arguments
Display the process ID, command, and command line arguments:
.Pp
.Bl -tag -width indent -compact
.It PID
process ID
.It COMM
command
.It ARGS
command line arguments (if available)
.El
.Ss File Descriptors
Display detailed information about each file descriptor referenced by a
process, including the process ID, command, file descriptor number, and
per-file descriptor object information, such as object type and file system
path:
.Pp
.Bl -tag -width indent -compact
.It PID
process ID
.It COMM
command
.It FD
file descriptor number or cwd/root/jail
.It T
file descriptor type
.It V
vnode type
.It FLAGS
file descriptor flags
.It REF
file descriptor reference count
.It OFFSET
file descriptor offset
.It PRO
network protocol
.It NAME
file path or socket addresses (if available)
.El
.Pp
The following file descriptor types may be displayed:
.Pp
.Bl -tag -width X -compact
.It c
crypto
.It f
fifo
.It h
shared memory
.It k
kqueue
.It m
message queue
.It p
pipe
.It s
socket
.It t
pseudo-terminal master
.It v
vnode
.El
.Pp
The following vnode types may be displayed:
.Pp
.Bl -tag -width X -compact
.It -
not a vnode
.It b
block device
.It c
character device
.It f
fifo
.It l
symbolic link
.It s
socket
.It x
revoked device
.El
.Pp
The following file descriptor flags may be displayed:
.Pp
.Bl -tag -width X -compact
.It r
read
.It w
write
.It a
append
.It s
async
.It f
fsync
.It n
non-blocking
.It d
direct I/O
.It l
lock held
.El
.Ss Kernel Thread Stacks
Display kernel thread stacks for a process, allowing further interpretation
of thread wait channels.
If the
.Fl k
flag is reeated, function offsets, not just function names, are printed.
.Pp
This feature requires
.Cd "options STACK"
or
.Cd "options DDB"
to be compiled into the kernel.
.Pp
.Bl -tag -width indent -compact
.It PID
process ID
.It TID
thread ID
.It COMM
command
.It TDNAME
thread name
.It KSTACK
kernel thread call stack
.El
.Ss Security Credentials
Display process credential information:
.Pp
.Bl -tag -width indent -compact
.It PID
process ID
.It COMM
command
.It EUID
effective user ID
.It RUID
real user ID
.It SVUID
saved user ID
.It EGID
effective group ID
.It RGID
real group ID
.It SVGID
saved group ID
.It GROUPS
group set
.El
.Ss Thread Information
Display per-thread information, including process ID, per-thread ID, name,
CPU, and execution state:
.Pp
.Bl -tag -width indent -compact
.It PID
process ID
.It TID
thread ID
.It COMM
command
.It TDNAME
thread name
.It CPU
current or most recent CPU run on
.It PRI
thread priority
.It STATE
thread state
.It WCHAN
thread wait channel
.El
.Ss Virtual Memory Mappings
Display process virtual memory mappings, including addresses, mapping
meta-data, and mapped object information:
.Pp
.Bl -tag -width indent -compact
.It PID
process ID
.It START
starting address of mapping
.It END
ending address of mapping
.It PRT
protection flags
.It RES
resident pages
.It PRES
private resident pages
.It REF
reference count
.It SHD
shadow page count
.It FL
mapping flags
.It TP
VM object type
.El
.Pp
The following protection flags may be displayed:
.Pp
.Bl -tag -width X -compact
.It r
read
.It w
write
.It x
execute
.El
.Pp
The following VM object types may be displayed:
.Pp
.Bl -tag -width XX -compact
.It --
none
.It dd
dead
.It df
default
.It dv
device
.It ph
physical
.It sw
swap
.It vn
vnode
.El
.Pp
The following mapping flags may be displayed:
.Pp
.Bl -tag -width X -compact
.It C
copy-on-write
.It N
needs copy
.El
.Sh EXIT STATUS
.Ex -std
.Sh SEE ALSO
.Xr fstat 1 ,
.Xr ps 1 ,
.Xr sockstat 1 ,
.Xr ddb 4 ,
.Xr stack 9
.Sh AUTHORS
.An Robert N M Watson
.Sh BUGS
Some field values may include spaces, which limits the extent to which the
output of
.Nm
may be mechanically parsed.
.Pp
The display of open file or memory mapping pathnames is implemented using the
kernel's name cache.
It therefore does not work for file systems
that do not use the name cache, such as
.Xr devfs 4 ,
or if the name is not present in the cache due to removal.
.Pp
.Nm
currently supports extracting data only from a live kernel, and not from
kernel crash dumps.