09-12-2013
Multithreading does not work that way; two cores can't cooperate to run a single-threaded program faster. Single-threaded programs will run slower on machines with lots of slower cores; we've had some puzzled folks ask us why their new machines have worse single-threaded benchmarks than their old ones.
But more cores means you can run more threads or processes at once without sharing time; more total work can be accomplished in the aggregate; but a program has to be designed with this in mind (or multiple instances of it run) to take advantage of this capability.
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timex(1) User Commands timex(1)
NAME
timex - time a command; report process data and system activity
SYNOPSIS
timex [-o] [ -p [-fhkmrt]] [-s] command
DESCRIPTION
The given command is executed; the elapsed time, user time and system time spent in execution are reported in seconds. Optionally, process
accounting data for the command and all its children can be listed or summarized, and total system activity during the execution interval
can be reported.
The output of timex is written on standard error.
OPTIONS
The following options are supported:
-o Report the total number of blocks read or written and total characters transferred by command and all its children. This option
works only if the process accounting software is installed.
-p List process accounting records for command and all its children. This option works only if the process accounting software is
installed. Suboptions f, h, k, m, r, and t modify the data items reported. The options are as follows:
-f Print the fork(2)/ exec(2) flag and system exit status columns in the output.
-h Instead of mean memory size, show the fraction of total available CPU time consumed by the process during its execution.
This ``hog factor'' is computed as (total CPU time)/(elapsed time).
-k Instead of memory size, show total kcore-minutes.
-m Show mean core size (the default).
-r Show CPU factor (user time/(system-time + user-time)).
-t Show separate system and user CPU times. The number of blocks read or written and the number of characters transferred
are always reported.
-s Report total system activity (not just that due to command) that occurred during the execution interval of command. All the data
items listed in sar(1) are reported.
EXAMPLES
Example 1: Examples of timex.
A simple example:
example% timex -ops sleep 60
A terminal session of arbitrary complexity can be measured by timing a sub-shell:
example% timex -opskmt sh
session commands
EOT
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWaccu |
+-----------------------------+-----------------------------+
SEE ALSO
sar(1), time(1), exec(2), fork(2), times(2), attributes( 5)
NOTES
Process records associated with command are selected from the accounting file /var/adm/pacct by inference, since process genealogy is not
available. Background processes having the same user ID, terminal ID, and execution time window will be spuriously included.
SunOS 5.10 14 Sep 1992 timex(1)