vi(1) [plan9 man page]

VI(1)							      General Commands Manual							     VI(1)

NAME

       vi, ki, xi - instruction simulators

SYNOPSIS

       vi [ textfile ]
       vi pid
       ki [ textfile ]
       ki pid
       xi [ textfile ]
       xi pid

DESCRIPTION

       Vi  simulates  the  execution  of a MIPS binary in a Plan 9 environment.  It has two main uses: as a debugger and as a statistics gatherer.
       Programs running under vi execute about two hundred times slower than normal--but faster than single stepping under db.	Ki and xi are sim-
       ilar to vi but interpret SPARC and ATT3210 binaries.  The following discussion refers to vi but applies to the others as well.

       Vi  will  simulate the execution of a named textfile.  It will also make a copy of an existing process with process id pid and simulate its
       continuation.

       As a debugger vi offers more complete information than db(1).  Tracing can be performed at the level  of  instructions,	system	calls,	or
       function  calls.   Vi  allows breakpoints to be triggered when specified addresses in memory are accessed.  A report of instruction counts,
       load delay fills and distribution is produced for each run.  Vi simulates the CPU's caches and MMU to assist the optimization of  compilers
       and programs.

       The  command  interface mirrors the interface to db; see db(1) for a detailed description.  Data formats and addressing are compatible with
       db except for disassembly: vi offers only MIPS (db -mmipsco) mnemonics for machine instructions.  Ki offers both Plan 9 and Sun SPARC  for-
       mats.

       Several extra commands allow extended tracing and printing of statistics:

       $t[0ics]
	      The t command controls tracing. Zero cancels all tracing options.

	      i      Enable instruction tracing

	      c      Enable call tracing

	      s      Enable system call tracing

       $i[itsp]
	      The i command prints statistics accumulated by all code run in this session.

	      i      Print instruction counts and frequency.

	      p      Print cycle profile.

	      t      (Vi only) Print TLB and cache statistics.

	      s      Print memory reference, working set and size statistics.

       :b[arwe]
	      Vi  allows  breakpoints  to be set on any memory location.  These breakpoints monitor when a location is accessed, read, written, or
	      equals a certain value.  For equality the compared value is the count (see db(1)) supplied to the command.

SOURCE

       /sys/src/cmd/vi etc.

SEE ALSO

       nm(1), db(1)

BUGS

       The code generated by the compilers is well supported, but some unusual instructions are unimplemented.	Some Plan 9 system calls  such	as
       rfork  cause simulated traps.  The floating point simulation makes assumptions about the interpreting machine's floating point support. The
       floating point conversions performed by vi may cause a loss of precision.

																	     VI(1)

KTRACE(1)						    BSD General Commands Manual 						 KTRACE(1)

NAME

     ktrace -- enable kernel process tracing

SYNOPSIS

     ktrace [-aCcdi] [-f trfile] [-g pgrp | -p pid] [-t trstr]
     ktrace [-adi] [-f trfile] [-t trstr] command

DESCRIPTION

     The ktrace command enables kernel trace logging for the specified processes.  Kernel trace data is logged to the file ktrace.out.	The kernel
     operations that are traced include system calls, namei translations, signal processing, and I/O.

     Once tracing is enabled on a process, trace data will be logged until either the process exits or the trace point is cleared.  A traced
     process can generate enormous amounts of log data quickly; It is strongly suggested that users memorize how to disable tracing before
     attempting to trace a process.  The following command is sufficient to disable tracing on all user owned processes, and, if executed by root,
     all processes:

	   $ ktrace -C

     The trace file is not human readable; use kdump(1) to decode it.

     The options are as follows:

     -a      Append to the trace file instead of recreating it.

     -C      Disable tracing on all user owned processes, and, if executed by root, all processes in the system.

     -c      Clear the trace points associated with the specified file or processes.

     -d      Descendants; perform the operation for all current children of the designated processes.

     -f file
	     Log trace records to file instead of ktrace.out.

     -g pgid
	     Enable (disable) tracing on all processes in the process group (only one -g flag is permitted).

     -i      Inherit; pass the trace flags to all future children of the designated processes.

     -p pid  Enable (disable) tracing on the indicated process id (only one -p flag is permitted).

     -t trstr
	     The string argument represents the kernel trace points, one per letter.  The following table equates the letters with the trace-
	     points:

	     c	   trace system calls
	     n	   trace namei translations
	     i	   trace I/O
	     s	   trace signal processing
	     u	   userland traces
	     w	   context switches

     command
	     Execute command with the specified trace flags.

     The -p, -g, and command options are mutually exclusive.

EXAMPLES

     # trace all kernel operations of process id 34
	   $ ktrace -p 34

     # trace all kernel operations of processes in process group 15 and # pass the trace flags to all current and future children
	   $ ktrace -idg 15

     # disable all tracing of process 65
	   $ ktrace -cp 65

     # disable tracing signals on process 70 and all current children
	   $ ktrace -t s -cdp 70

     # enable tracing of I/O on process 67
	   $ ktrace -ti -p 67

     # run the command "w", tracing only system calls
	   $ ktrace -tc w

     # disable all tracing to the file "tracedata"
	   $ ktrace -c -f tracedata

     # disable tracing of all processes owned by the user
	   $ ktrace -C

SEE ALSO

     kdump(1)

BUGS

     Only works if file is a regular file.

HISTORY

     The ktrace command appeared in 4.4BSD.

BSD
								   June 6, 1993 							       BSD