dxthreads(1)dxthreads(1)NAME
dxthreads, VisualThreads - Visual Threads
SYNOPSIS
VisualThreads [option]... [program [arguments]]
dxthreads [option]... [program [arguments]]
DESCRIPTION
Visual Threads assists application developers in analyzing the behavior
of their multithreaded applications. Visual Threads collects detailed
information about the significant state changes that occur during the
running of a POSIX-threaded application, allows you to view these
changes as they occur and provides automated dynamic analysis algo‐
rithms to diagnose common problems of multithreading including: dead‐
lock, race conditions, and other programming errors. The major fea‐
tures of Visual Threads include:
· Automatic event monitoring and exception condition detection. A
number of preset conditions will be monitored. These look for
logic problems, data protection problems (Tru64 UNIX only), per‐
formance problems, and deadlock conditions.
· Scrollable display of events as they occur, with user definable
filtering.
· Stop on detection of exception conditions. The user has several
options at this point, including entering the debugger in the
appropriate program context.
· Real-time dynamic monitoring of pthread objects (threads, mutexes,
etc) attributes.
· Easy access by the user to object-level statistics and current
state information including resource usage, such as what mutexes
does a particular thread hold.
· Record events to a log file for later playback and analysis.
· User-defined rules will enable users to specify the criteria for
exception conditions.
For more information, see the Visual Threads online Help.
OPTIONS-d display
Specifies the X Window System server to use for display. The
specification is in the form hostname:display. For example:
% VisualThreads -display host1.hp.com:0
-help, +help
Display the Visual Threads help viewer containing the online
documentation.
-mxx Sets the maximum size of the memory allocation pool (the
garbage collected heap) to x. The default is 64 megabytes of
memory. x must be greater than or equal to 1000 bytes.
By default, x is measured in bytes. You can specify x in
either kilobytes or megabytes by appending the letter k for
kilobytes or the letter m for megabytes.
-msx Sets the startup size of the memory allocation pool (the
garbage collected heap) to x. The default is 1 megabyte of
memory. x must be > 1000 bytes.
By default, x is measured in bytes. You can specify x in
either kilobytes or megabytes by appending the letter k for
kilobytes or the letter m for megabytes.
-version Print out the build version number.
-v Turn on verbose mode.
-Joption Pass the specified option to the Java Runtime Environment com‐
mand. For example, to pass the -help option to the Java Run‐
time Environment command, append it to the -J option as shown
below.
% VisualThreads -J-help
program [arguments]
Specifies the application program and its arguments to set as
the initial analysis target. Hitting the Play button will
start the analysis.
ENVIRONMENT VARIABLES
The following environment variables affect the execution of Visu‐
alThreads:
VT_TERMINAL
Determines the preferred terminal emulator for use when ana‐
lyzing a running application, or invoking a command line
debugger. If VT_TERMINAL is defined but has no value, then no
terminal emulator is started and any application input/output
will be to the terminal from which VisualThreads was invoked.
VT_DEBUG Determines the preferred debugger to debug a running applica‐
tion. If this variable is not defined, on Tru64 UNIX the
default debugger is ladebug, and on Linux & HP-UX the default
is gdb. If this variable is defined, it should be either a
full path specification of a preferred debugger, or a command
which can be resolved via your path. The debugger supplied
must have the ability to attach to a program given a pid argu‐
ment. By default the debugger is invoked as: $VT_DEBUG -pid
{pid} {program}, however, gdb, wdb, xxgdb, and ddd will be
invoked as: $VT_DEBUG {program} {pid}. For more details on
debugger interaction, see the Release Notes, and on Linux, the
README file.
VT_CACHE_SIZE
Controls the number of events that VisualThreads saves in mem‐
ory during analysis. By default, VisualThreads saves 10000
events. When analyzing a trace file, a larger value may
improve interactive performance. When analyzing a running
application, this value provides the upper limit on how far
back you can scroll the Event Window.
EDITOR If this environment variable is defined, VisualThreads will
enable an Edit button on the Source window. When the Edit
button is pressed, the specified editor will be launched in a
terminal window, using the terminal defined by VT_TERMINAL,
with the parameters +line_number filename.
VT_CLIENT_EDITOR
If you use a graphical client-server editor such as emacs, you
can define the environment variable VT_CLIENT_EDITOR with the
value of the client editor command. If this variable is
defined, VisualThreads will not create a Source window;
instead it will launch the specified client editor command to
view the source with the parameters +line_number filename to
position the editor at the appropriate line in the source
file. If both EDITOR and VT_CLIENT_EDITIOR are defined,
VT_CLIENT_EDITOR has precedence.
RELATED INFORMATION
HP-UX Commands: vttrace(1), X(1), gdb(1), wdb(1), pthread(3T).
Linux Commands: vttrace(1), X(1X), gdb(1)
Tru64 UNIX Commands: vttrace(1), vti(1), ladebug(1), pthread(3),
dtterm(1), X(1X).
dxthreads(1)