dcpidiff - Compares two sets of profiles for a procedure
dcpidiff [global options] procedure-name -set [set options]
image-name -set [set options] image-name
- Print out usage information.
- Print out the version number.
- Verbose. Print out additional information.
- Print out statistics by source line number. If the image-name of
the two sets are the same, then the default is to print out the statistics
by basic block. If the image-name is different, then the statistics
can only be printed by source line number.
- -compare type
- Specify the kind of information compared. The type is a
comma-separated list of the following keywords: cpi,
frequency, stalls, static_stalls, dynamic_stalls
or all. The default is to compare CPI only.
- Denote the start of a set of sample files. All samples within a set are
combined, and samples across different sets are compared.
- Compare low, medium, and high-confidence data.
- Compare only high-confidence data. (Default is to compare medium and
- -cross_procedure [optimistic | pessimistic | selective]
- Choose what assumption to make when encountering a procedure call
boundary while looking for reasons to explain dynamic stalls. A procedure
call boundary is either a call made by the procedure being analyzed or the
beginning or end of that procedure. With pessimistic, we assume that
whatever happens outside the analyzed procedure can cause a dynamic stall
inside it. With optimistic, we assume that it cannot. With
selective, the assumption is based on standard procedure call
convention. (The default is optimistic.)
PROFILE FILE FLAGS
By default, this command automatically finds all of the relevant profile
files. The following options can be used to guide the search for the profile
- -db <directory name>
- Search for profile files in the specified profile database directory.
The directory name should be the same name as the one specified when
dcpid was started. That is, the named directory should contain a set
of epochs. If this option is not specified, the directory name is obtained
from the DCPIDB logical name. If neither of these methods succeeds in finding the appropriate directory, and no
explicit set of profile files is provided via the -profiles option,
then the command fails.
- -epoch latest
- Search for profile files in the latest epoch. This is the default.
- -epoch latest-k
- Search for profile files in the "k+1"th oldest epoch. For example,
search in the third last epoch if "-epoch latest-2" is specified.
- -epoch all
- Search for profile files in all epochs.
- -epoch <name>
- Search for profile files in the named epoch. The epoch name should be
the name of a subdirectory corresponding to a single epoch within the
profile database directory. Epoch subdirectory names usually take the form
YYYYMMDDHHMM (year-month-day-hours-minutes). For example, an epoch
started on December 4, 2002 at 23:34 is named 200212042334. If an
epoch is given a symbolic name by creating a symbol link to the actual epoch
directory, then the symbolic name can also be used as an argument to the
- -events all
- Search for profile files corresponding to all event types such as
cycles, icache misses, errors in branch predictions, etc. This is the default.
- -events type(+type)*
- Search for profiles files for the specified event types. For example,
search for cycles, icache misses, and data cache misses when the option
-events cycles+imiss+dmiss is specified.
- -events all(-type)*
- Search for profile files for all event types except for the specified
types. For example, search for all event types except for branch
mispredictions when the option -events all-branchmp is specified.
- -label <label>
- Search for profile files with the specified label (see
dcpilabel). If no labels are specified on the command line, profile
file labels are ignored entirely. If any labels are specified on the command
line (this option can be repeated several times), only profile files that
have one of the specified labels are used.
- -profiles <file names...> --
- Use just the profile files named by the specified file names. The list
of profile file names can be terminated either via --, or by the
end of the option list. The command prints an error message and fails if the
-profiles option is used in conjunction with any of the earlier
automatic profile finding options. (Use either the automatic profile lookup
mechanism, or explicitly name the profile file with the -profile
option, but not both.)
Dcpidiff compares two sets of profiles for a procedure and prints out
various statistics. It can compare the CPI, frequency, and static and dynamic
stall cycles. If the images for the two sets of profiles are the same, then it
compares them by basic block. If the images differ, then it compares by source
For each basic block (or source line) it prints the normalized range (that
is, the difference between the values over the sum of the values, expressed as a
percentage), the two values and the ratio of the values. All entries are
sorted by the normalized range so that the focus is on the entries that differ
the most. The available options for each of the two sets is similar to the
options for dcpicalc(1).
Input parameter procedure-name can be the ascii procedure name,
an address within a procedure (in C syntax, for example, 0x20000 is hex address 20000),
or an explicit address range (useful when analyzing images without debug symbol information;
for example, 0x20000:0x200c0).
- dcpidiff the_proc -set <image-name> -epoch latest -set
<image-name> -epoch latest-1
Use dcpidiff to compare the CPI of procedure the_proc in two
different sets of sample files.
dcpid(1), dcpidiff(1), dcpiformat(4), dcpilist(1),
For more information, see the HP Digital Continuous Profiling Infrastructure
project home page
Last modified: April 8, 2004