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kcbench
Langue: en
Version: 369116 (fedora - 01/12/10)
Section: 1 (Commandes utilisateur)
NAME
kcbench - Kernel compile benchmarkSYNOPSIS
kcbench [options]
DESCRIPTION
Compiles a Linux kernel to benchmark a system or test its stabilityOPTIONS
- -d, --compiledir <path>
Use the subdirectory kcbench in <path>/ when compiling results -- passes 'O=<path> /kcbench/' to make when calling it to compile a kernel; use a tempdir if not given-r, --detailedresults
Print more detailed results-a, --ignore-running-apps
Do not warn if cron or other daemons run in the background; the results might not be stable when those run and call jobs that consume CPU time or do a lot of I/O-i, --infinite
run endlessly to test system stability-n, --iterations <int>
Number or iterations per number of jobs (default: 3)-j, --jobs <int>
Number of jobs to use ('make -j #'); option can be given multiple times (default: number of CPUs * 2)-c, --no-cachefill
Omit the initial kernel compile to fill caches; saves time, but first result might be slightly lower then the following ones-v, --verbose
Increase verboselevel; option can be given multiple times-l, --savefailedlogs <path>
Save log of failed compile runs in <path>-s, --src (<path>|<version>)
Take sources in <path> or from /usr/share/kcdata/linux-<version>-h, --help
Show usage-V, --version
Output program version
ENVIRONMENT
Kcbench looks for a kernel to compile in /usr/share/kcbench-data and will take the one that a "ls usr/share/kcbench-data | head -n 1" outputs by defaultEXAMPLE
To compile the default kernel 3 times in a row run:$ kcbenchTo compile the defaukt kernel 3 times with 2 jobs and 3 times with 4 jobs run
$ kcbench --iterations 3 --jobs 2 --jobs 4
RESULTS
By default the line you are looking for is this:Run 1 (-j 4): 5775 (e:173.15P:192% U:263.49 S:69.42 F:0)Here it has taken 173.15 seconds real time (e) to compile the kernel; the CPU-Usage (P) was 192 percent; user time (U) spend was 296.49 and sys time (S) 69.42 and there we no major page faults (see the info or man pages for time for details about the notation).
As most people prefer if higher numbers mean faster systems -- to give them what they expect kcbench divides 1000000 by the real time spend, which results in 5775 kcbench points (1000000/173.15) in this example.
When running with "-r|--detailedresults" you'll get more detailed results:
Run 1 (-j 4): 6662 (e:150.10 P:197% U:259.51 S:36.38 F:0) Elapsed Time(E): 2:30.10 (150.10 seconds) Kernel time (S): 36.38 seconds User time (U): 259.51 seconds CPU usage (P): 197% Major page faults (F): 0 Minor page faults (R): 9441809 Context switches involuntarily (c): 69031 Context switches voluntarily (w): 46955
HINTS
- *
- sometimes using exactly as much jobs as processors in the system results in a result that's a bit faster than the default (two times the number of processors)
- *
- the compiler has a huge impact on the results; if you compare results from different machines make sure they use a similar one. The running kernel and its settings also have a impact on the results. Thus it's the best not to compare different distributions/different patch levels.
- *
- the kernel that is being compiled of course has a huge impact as well; compare only results where you compiled the same kernel version
SEE ALSO
time(1).BUGS
None know, but there are likely someAUTHOR
Thorsten Leemhuis <fedora [AT] leemhuis [DOT] info>Contenus ©2006-2024 Benjamin Poulain
Design ©2006-2024 Maxime Vantorre