SCONS-TIME(1) SCons 4.9.1 SCONS-TIME(1)

NAME

scons-time - generate and display SCons timing information

SYNOPSIS

scons-time subcommand [options...] [arguments...]

GENERATING TIMING INFORMATION

scons-time run [-hnqv] [-f FILE] [--number=NUMBER] [--outdir=OUTDIR]
[-p STRING] [--python=PYTHON] [-s DIR] [--scons=SCONS] [--svn=URL]
[ARGUMENTS]

Extracting Function Timings

scons-time func [-h] [--chdir=DIR] [-f FILE] [--fmt=FORMAT]
[--func=NAME] [-p STRING] [-t NUMBER] [--title= TITLE] [ARGUMENTS]

Extracting Memory Statistics

scons-time mem [-h] [--chdir=DIR] [-f FILE] [--fmt=FORMAT] [-p
STRING] [--stage=STAGE] [-t NUMBER] [--title=TITLE] [ARGUMENTS]

Extracting Object Counts

scons-time obj [-h] [--chdir=DIR] [-f FILE] [--fmt=FORMAT] [-p
STRING] [--stage=STAGE] [-t NUMBER] [--title=TITLE] [ARGUMENTS]

Extracting Execution Times

scons-time time [-h] [--chdir=DIR] [-f FILE] [--fmt=FORMAT] [-p
STRING] [-t NUMBER] [--title=TITLE] [--which=WHICH] [ARGUMENTS]

Help Text

scons-time help SUBCOMMAND [...]

DESCRIPTION

The scons-time command runs an SCons configuration through a standard
set of profiled timings and can extract and graph information from
the resulting profiles and log files of those timings. The action to
be performed by the scons-time script is specified by a subcommand,
the first argument on the command line. See the SUBCOMMANDS section
below for information about the operation of specific subcommands.

The basic way to use scons-time is to run the scons-time run
subcommand (possibly multiple times) to generate profile and log file
output, and then use one of the other subcommands to display the
results captured in the profiles and log files for a particular kind
of information: function timings (the scons-time func subcommand),
total memory used (the scons-time mem subcommand), object counts (the
scons-time obj subcommand) and overall execution time (the scons-time
time subcommand). Options exist to place and find the profiles and
log files in separate directories, to generate the output in a format
suitable for graphing with the gnuplot(1) program, and so on.

There are two basic ways the scons-time run subcommand is intended to
be used to gather timing statistics for a configuration. One is to
use the --svn= option to test a configuration against a list of
revisions from the SCons Subversion repository. This will generate a
profile and timing log file for every revision listed with the
--number= option, and can be used to look at the impact of committed
changes to the SCons code base on a particular configuration over
time.

The other way is to profile incremental changes to a local SCons code
base during a development cycle--that is, to look at the performance
impact of changes you're making in the local tree. In this mode, you
run the scons-time run subcommand without the --svn= option, in which
case it simply looks in the profile/log file output directory (the
current directory by default) and automatically figures out the next
run number for the output profile and log file. Used in this way, the
development cycle goes something like: make a change to SCons; run
scons-time run to profile it against a specific configuration; make
another change to SCons; run scons-time run again to profile it; etc.

OPTIONS

The scons-time command only supports a few global options:

-h, --help
Displays the global help text and exits, identical to the
scons-time help subcommand.

-V, --version
Displays the scons-time version and exits.

Most functionality is controlled by options to the individual
subcommands. See the next section for information about individual
subcommand options.

SUBCOMMANDS

The scons-time command supports the following individual subcommands.

The func Subcommand

scons-time func [-h] [--chdir=DIR] [-f FILE] [--fmt=FORMAT]
[--func=NAME] [-p STRING] [-t NUMBER] [--title= TITLE] [ARGUMENTS]

The scons-time func subcommand displays timing information for a
specific Python function within SCons. By default, it extracts
information about the _main() function, which includes the Python
profiler timing for all of SCons.

The scons-time func subcommand extracts function timing information
from all the specified file arguments, which should be Python
profiler output files. (Normally, these would be *.prof files
generated by the scons-time run subcommand, but they can actually be
generated by any Python profiler invocation.) All file name arguments
will be globbed for on-disk files.

If no arguments are specified, then function timing information will
be extracted from all *.prof files, or the subset of them with a
prefix specified by the -p option.

Options include:

-C DIRECTORY, --chdir=DIRECTORY
Changes to the specified DIRECTORY before looking for the
specified files (or files that match the specified patterns).

-f FILE, --file=FILE
Reads configuration information from the specified FILE.

-fmt=FORMAT, --format=FORMAT
Reports the output in the specified FORMAT. The formats currently
supported are ascii (the default) and gnuplot.

--func=NAME
Extracts timings for the specified function NAME. The default is
to report cumulative timings for the _main() function, which
contains the entire SCons run.

-h, --help
Displays help text for the scons-time func subcommand.

-p STRING, --prefix=STRING
Specifies the prefix string for profiles from which to extract
function timing information. This will be used to search for
profiles if no arguments are specified on the command line.

-t NUMBER, --tail=NUMBER
Only extracts function timings from the last NUMBER files.

The help Subcommand

scons-time help SUBCOMMAND [...] The help subcommand prints help text
for any other subcommands listed as later arguments on the command
line.

The mem Subcommand

scons-time mem [-h] [--chdir=DIR] [-f FILE] [--fmt=FORMAT] [-p
STRING] [--stage=STAGE] [-t NUMBER] [--title=TITLE] [ARGUMENTS]

The scons-time mem subcommand displays how much memory SCons uses.

The scons-time mem subcommand extracts memory use information from
all the specified file arguments, which should be files containing
output from running SCons with the --debug=memory option. (Normally,
these would be *.log files generated by the scons-time run
subcommand.) All file name arguments will be globbed for on-disk
files.

If no arguments are specified, then memory information will be
extracted from all *.log files, or the subset of them with a prefix
specified by the -p option.

-C DIR, --chdir=DIR
Changes to the specified DIRECTORY before looking for the
specified files (or files that match the specified patterns).

-f FILE, --file=FILE
Reads configuration information from the specified FILE.

-fmt=FORMAT, --format=FORMAT
Reports the output in the specified FORMAT. The formats currently
supported are ascii (the default) and gnuplot.

-h, --help
Displays help text for the scons-time mem subcommand.

-p STRING, --prefix=STRING
Specifies the prefix string for log files from which to extract
memory usage information. This will be used to search for log
files if no arguments are specified on the command line.

--stage=STAGE
Prints the memory used at the end of the specified STAGE:
pre-read (before the SConscript files are read), post-read ,
(after the SConscript files are read), pre-build (before any
targets are built) or post-build (after any targets are built).
If no --stage option is specified, the default behavior is
post-build, which reports the final amount of memory used by
SCons during each run.

-t NUMBER, --tail=NUMBER
Only reports memory statistics from the last NUMBER files.

The obj Subcommand

scons-time obj [-h] [--chdir=DIR] [-f FILE] [--fmt=FORMAT] [-p
STRING] [--stage=STAGE] [-t NUMBER] [--title=TITLE] [ARGUMENTS]

The scons-time obj subcommand displays how many objects of a specific
named type are created by SCons.

The scons-time obj subcommand extracts object counts from all the
specified file arguments, which should be files containing output
from running SCons with the --debug=count option. (Normally, these
would be *.log files generated by the scons-time run subcommand.) All
file name arguments will be globbed for on-disk files.

If no arguments are specified, then object counts will be extracted
from all *.log files, or the subset of them with a prefix specified
by the -p option.

-C DIR, --chdir=DIR
Changes to the specified DIRECTORY before looking for the
specified files (or files that match the specified patterns).

-f FILE, --file=FILE
Reads configuration information from the specified FILE.

-fmt=FORMAT, --format=FORMAT
Reports the output in the specified FORMAT. The formats currently
supported are ascii (the default) and gnuplot.

-h, --help
Displays help text for the scons-time obj subcommand.

-p STRING, --prefix=STRING
Specifies the prefix string for log files from which to extract
object counts. This will be used to search for log files if no
arguments are specified on the command line.

--stage=STAGE
Prints the object count at the end of the specified STAGE:
pre-read (before the SConscript files are read), post-read ,
(after the SConscript files are read), pre-build (before any
targets are built) or post-build (after any targets are built).
If no --stage option is specified, the default behavior is
post-build, which reports the final object count during each run.

-t NUMBER, --tail=NUMBER
Only reports object counts from the last NUMBER files.

The run Subcommand

scons-time run [-hnqv] [-f FILE] [--number=NUMBER] [--outdir=OUTDIR]
[-p STRING] [--python=PYTHON] [-s DIR] [--scons=SCONS] [--svn=URL]
[ARGUMENTS] The scons-time run subcommand is the basic subcommand for
profiling a specific configuration against a version of SCons.

The configuration to be tested is specified as a list of files or
directories that will be unpacked or copied into a temporary
directory in which SCons will be invoked. The scons-time run
subcommand understands file suffixes like .tar, .tar.gz, .tgz and
.zip and will unpack their contents into a temporary directory. If
more than one argument is specified, each one will be unpacked or
copied into the temporary directory "on top of" the previous archives
or directories, so the expectation is that multiple specified
archives share the same directory layout.

Once the file or directory arguments are unpacked or copied to the
temporary directory, the scons-time run subcommand runs the requested
version of SCons against the configuration three times:

Startup
SCons is run with the --help option so that just the SConscript
files are read, and then the default help text is printed. This
profiles just the perceived "overhead" of starting up SCons and
processing the SConscript files.

Full build
SCons is run to build everything specified in the configuration.
Specific targets to be passed in on the command line may be
specified by the targets keyword in a configuration file; see
below for details.

Rebuild
SCons is run again on the same just-built directory. If the
dependencies in the SCons configuration are correct, this should
be an up-to-date, "do nothing" rebuild.

Each invocation captures the output log file and a profile.

The scons-time run subcommand supports the following options:

-f FILE, --file=FILE
Reads configuration information from the specified FILE. This
often provides a more convenient way to specify and collect
parameters associated with a specific timing configuration than
specifying them on the command line. See the CONFIGURATION FILE
section below for information about the configuration file
parameters.

-h, --help
Displays help text for the scons-time run subcommand.

-n, --no-exec
Do not execute commands, just printing the command-line
equivalents of what would be executed. Note that the scons-time
script actually executes its actions in Python, where possible,
for portability. The commands displayed are UNIX equivalents of
what it's doing.

--number=NUMBER
Specifies the run number to be used in the names of the log files
and profile outputs generated by this run.

When used in conjunction with the --svn=URL option, NUMBER specifies
one or more comma-separated Subversion revision numbers that will be
retrieved automatically from the Subversion repository at the
specified URL. Ranges of delta or revision numbers may be specified
be separating two numbers with a hyphen (-).

Example:

% scons-time run --svn=http://scons.tigris.org/svn/trunk --num=1247,1249-1252 .

-p STRING, --prefix=STRING
Specifies the prefix string to be used for all of the log files
and profiles generated by this run. The default is derived from
the first specified argument: if the first argument is a
directory, the default prefix is the name of the directory; if
the first argument is an archive (tar or zip file), the default
prefix is the base name of the archive, that is, what remains
after stripping the archive suffix (.tgz, .tar.gz or .zip).

--python=PYTHON
Specifies a path to the Python executable to be used for the
timing runs. The default is to use the same Python executable
that is running the scons-time command itself.

-q, --quiet
Suppresses display of the command lines being executed.

-s DIR, --subdir=DIR
Specifies the name of directory or subdirectory from which the
commands should be executed. The default is XXX

--scons=SCONS
Specifies a path to the SCons script to be used for the timing
runs. The default is XXX

--svn=URL, --subversion=URL
Specifies the URL of the Subversion repository from which the
version(s) of scons being timed will be extracted. When --svn is
specified, the --number=NUMBER option specifies revision numbers
that will be tested. Output from each invocation run will be
placed in file names that match the Subversion revision numbers.
If the --number= option is not specified, then the default
behavior is to time the HEAD of the specified URL.

-v, --verbose
Displays the output from individual commands to the screen (in
addition to capturing the output in log files).

The time Subcommand

scons-time time [-h] [--chdir=DIR] [-f FILE] [--fmt=FORMAT] [-p
STRING] [-t NUMBER] [--title=TITLE] [--which=WHICH] [ARGUMENTS]

The scons-time time subcommand displays SCons execution times as
reported by the scons --debug=time option.

The scons-time time subcommand extracts SCons timing from all the
specified file arguments, which should be files containing output
from running SCons with the --debug=time option. (Normally, these
would be *.log files generated by the scons-time run subcommand.) All
file name arguments will be globbed for on-disk files.

If no arguments are specified, then execution timings will be
extracted from all *.log files, or the subset of them with a prefix
specified by the -p option.

-C DIR, --chdir=DIR
Changes to the specified DIRECTORY before looking for the
specified files (or files that match the specified patterns).

-f FILE, --file=FILE
Reads configuration information from the specified FILE.

-fmt=FORMAT, --format=FORMAT
Reports the output in the specified FORMAT. The formats currently
supported are ascii (the default) and gnuplot.

-h, --help
Displays help text for the scons-time time subcommand.

-p STRING, --prefix=STRING
Specifies the prefix string for log files from which to extract
execution timings. This will be used to search for log files if
no arguments are specified on the command line.

-t NUMBER, --tail=NUMBER
Only reports object counts from the last NUMBER files.

--which=WHICH
Prints the execution time for the specified WHICH value: total
(the total execution time), SConscripts (total execution time for
the SConscript files themselves), SCons (execution time in SCons
code itself) or commands (execution time of the commands and
other actions used to build targets). If no --which option is
specified, the default behavior is total, which reports the total
execution time for each run.

CONFIGURATION FILE

Various scons-time subcommands can read information from a specified
configuration file when passed the -f or --file options. The
configuration file is actually executed as a Python script. Setting
Python variables in the configuration file controls the behavior of
the scons-time script more conveniently than having to specify
command-line options or arguments for every run, and provides a handy
way to "shrink-wrap" the necessary information for producing (and
reporting) consistent timing runs for a given configuration.

archive_list
A list of archives (files or directories) that will be copied to
the temporary directory in which SCons will be invoked. .tar,
.tar.gz, .tgz and .zip files will have their contents unpacked in
the temporary directory. Directory trees and files will be copied
as-is.

initial_commands
A list of commands that will be executed before the actual timed
scons runs. This can be used for commands that are necessary to
prepare the source tree-for example, creating a configuration
file that should not be part of the timed run.

key_location
The location of the key on Gnuplot graphing information generated
with the --format=gnuplot option. The default is bottom left.

prefix
The file name prefix to be used when running or extracting timing
for this configuration.

python
The path name of the Python executable to be used when running or
extracting information for this configuration. The default is the
same version of Python used to run the SCons

scons
The path name of the SCons script to be used when running or
extracting information for this configuration. The default is
simply scons.

scons_flags
The scons flags used when running SCons to collect timing
information. The default value is --debug=count --debug=memory
--debug=time --debug=memoizer.

scons_lib_dir, scons_wrapper, startup_targets, subdir
The subdirectory of the project into which the scons-time script
should change before executing the SCons commands to time.

subversion_url
The Subversion URL from

svn
The subversion executable used to check out revisions of SCons to
be timed. The default is simple svn.

svn_co_flag, tar, targets
A string containing the targets that should be added to the
command line of every timed scons run. This can be used to
restrict what's being timed to a subset of the full build for the
configuration.

targets0, targets1, targets2, title, unzip, verbose, vertical_bars

Example

Here is an example scons-time configuration file for a hypothetical
sample project:

# The project doesn't use SCons natively (yet), so we're
# timing a separate set of SConscript files that we lay
# on top of the vanilla unpacked project tarball.
arguments = ['project-1.2.tgz', 'project-SConscripts.tar']

# The subdirectory name contains the project version number,
# so tell scons-time to chdir there before building.
subdir = 'project-1.2'

# Set the prefix, so output log files and profiles are named:
# project-000-[012].{log,prof}
# project-001-[012].{log,prof}
# etc.
prefix = 'project'

# The SConscript files being tested don't do any SConf
# configuration, so run their normal ./configure script
# before we invoke SCons.
initial_commands = [
'./configure',
]

# Only time building the bin/project executable.
targets = 'bin/project'

# Time against SCons revisions of the branches/core branch
subversion_url = 'http://scons.tigris.org/svn/scons/branches/core'

ENVIRONMENT

The scons-time script uses the following environment variables:

PRESERVE
If this value is set, the scons-time script will not remove the
temporary directory or directories in which it builds the
specified configuration or downloads a specific version of SCons.

SEE ALSO

gnuplot(1), scons(1)

AUTHORS

Steven Knight <knight at baldmt dot com>

SCons 4.9.1 03/27/2025 SCONS-TIME(1)