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trace(1) [ultrix man page]

trace(1)						      General Commands Manual							  trace(1)

Name
       trace - trace system calls of programs

Syntax
       trace [options] cmd args...

Description
       The  command  with  no flag arguments traces for the given cmd and args all system calls made and prints a time stamp, the PID, call and/or
       return values and arguments and puts its output in the file trace.dump.

Options
       -f filename
	       Puts dump in file filename.

       -z      Echos arguments only.

       Only one of the following option arguments can be specified at one time.

       -c#     Traces given PIDs and their children.  Up to sixteen PIDs can be specified.

       -g#     Traces given groups only.  Up to sixteen Group IDs can be specified.

       -p#     Traces given PIDs only.	Up to sixteen PIDs can be specified.

       -s#     Traces given system calls only.	Up to sixteen PIDs can be specified.

       -u#     Traces given UIDs only.	Up to sixteen PIDs can be specified.

Examples
       trace -f ls.dump ls -l /dev >ls.out
       runs the cmd ls -l /dev and puts the trace in ls.dump and output in ls.out.
       trace -f csh.trace -p $$ &
       will trace your login shell in the background. To stop the trace just send it a termination signal (that is, kill -TERM trace_pid).

Restrictions
       Due to security, no one, not even the super-user can trace anyone else's programs. This sort of negates some of the usefulness  of  the	-g
       and -u flags.

       The program cannot be traced.

       Only 16 numbers can be given to the -c, -p, -g, -u, and -s flags.

       The kernel configuration file must contain the following:
       options	       SYS_TRACE
       pseudo-device   sys_trace

       In addition, the superuser must use the following command sequence to create the device:
       cd /dev
       MAKEDEV trace
       If both lines are not in the configuration file or if the device is not made, the message "Cannot open /dev/trace" appears.

Files
       /dev/trace     read only character special device for reading syscall data.

       trace.dump     default file for the system call trace data.

See Also
       open(2), close(2), ioctl(2), select(2), read(2), trace(5)

																	  trace(1)

Check Out this Related Man Page

iowatcher(1)						      General Commands Manual						      iowatcher(1)

NAME
iowatcher - Create visualizations from blktrace results SYNOPSIS
iowatcher OPTIONS... DESCRIPTION
iowatcher graphs the results of a blktrace run. It can graph the result of an existing blktrace, start a new blktrace, or start a new blk- trace and a benchmark run. It can then create an image or movie of the IO from a given trace. iowatcher can produce either SVG files or movies in mp4 format (with ffmpeg) or ogg format (with png2theora). OPTIONS
--help Print a brief usage summary. -d, --device <device> Controls which device you are tracing. You can only trace one device at a time for now. It is sent directly to blktrace, and only needed when you are making a new trace. -D, --blktrace-destination <destination> Destination for blktrace. -p, --prog <program> Program to run while blktrace is run. -K, --keep-movie-svgs Keep the SVG files generated for movie mode. -t, --trace <file|directory> Controls the name of the blktrace file. iowatcher uses a dump from blkparse, so -t tries to guess the name of the corresponding per CPU blktrace data files if the dump file doesn't already exist. If you want more than one trace in a given graph, you can specify -t more than once. If a directory is specified, iowatcher will use the name of the directory as the base name of the dump file and all trace files found inside the directory will be processed. -l, --label <label> Sets a label in the graph for a trace file. The labels are added in the same order the trace files are added. -m, --movie [spindle|rect] Create a movie. The file format depends on the extension used in the -o filename.* option. If you specify an .ogv or .ogg exten- sion, the result will be Ogg Theora video, if png2theora is available. If you use an .mp4 extension, the result will be an mp4 video if ffmpeg is available. You can use any other extension, but the end result will be an mp4. You can use --movie=spindle or --movie=rect, which changes the style of the IO mapping. -T, --title <title> Set a title to be placed at the top of the graph. -o, --output <file> Output filename (default: trace.svg). -r, --rolling <seconds> Control the duration for the rolling average. iowatcher tries to smooth out bumpy graphs by averaging the current second with sec- onds from the past. Larger numbers here give you flatter graphs. -h, --height <height> Set the height of each graph -w, --width <width> Set the width of each graph -c, --columns <columns> Numbers of columns in graph output -x, --xzoom <min:max> Limit processed time range to min:max -y, --yzoom <min:max> Limit processed sectors to min:max -a, --io-plot-action <action> Plot given action (one of Q,D,C) in IO graph -P, --per-process-io Distinguish between processes in IO graph -O, --only-graph <graph> Add a single graph to the output (see GRAPHS). By default all the graphs are included, but with -O you get only the graphs you ask for. -O may be used more than once. -N, --no-graph <type> Remove a single graph from the output (see GRAPHS). This may also be used more than once. GRAPHS
Choices for -O and -N are: io, tput, latency, queue_depth, iops, cpu-sys, cpu-io, cpu-irq, cpu-user, cpu-soft EXAMPLES
Generate graph from the existing trace.dump: iowatcher -t trace.dump -o trace.svg Skip the IO graph: iowatcher -t trace.dump -o trace.svg -N io Only graph tput and latency: iowatcher -t trace.dump -o trace.svg -O tput -O latency Generate a graph from two runs, and label them: iowatcher -t ext4.dump -t xfs.dump -l Ext4 -l XFS -o trace.svg Run a fio benchmark and store the trace in trace.dump, add a title to the top, use /dev/sda for blktrace: iowatcher -d /dev/sda -t trace.dump -T 'Fio Benchmark' -p 'fio some_job_file' Make a movie from an existing trace: iowatcher -t trace --movie -o trace.mp4 iowatcher(1)

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