mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/
synced 2026-11-10 20:48:12 +00:00
No description
- C 96.8%
- Assembly 0.9%
- Rust 0.7%
- Shell 0.6%
- Python 0.5%
- Other 0.3%
c00d476cbc
Some of AMD ZEN4 APU/CPU have support for adjusting the CPU core
clock more quickly and presicely according to CPU work loading.
This is advertised by the Fast CPPC x86 feature.
This change will only be effective in the *passive mode* of
AMD pstate driver. From the test results of different
transition delay values, 600us is chosen to make a balance
between performance and power consumption.
Some test results on AMD Ryzen 7840HS(Phoenix) APU:
1. Tbench
(Energy less is better, Throughput more is better,
PPW--Performance per Watt more is better)
============= =================== ============== =============== ============== =============== ============== =============== ===============
Trans Delay Tbench governor:schedutil, 3-iterations average
============= =================== ============== =============== ============== =============== ============== =============== ===============
1000us Clients 1 2 4 8 12 16 32
Energy/Joules 2010 2804 8768 17171 16170 15132 15027
Throughput/(MB/s) 114 259 1041 3010 3135 4851 4605
PPW 0.0567 0.0923 0.1187 0.1752 0.1938 0.3205 0.3064
600us Clients 1 2 4 8 12 16 32
Energy/Joules 2115 (5.22%) 2388 (-14.84%) 10700(22.03%) 16716 (-2.65%) 15939 (-1.43%) 15053 (-0.52%) 15083 (0.37% )
Throughput/(MB/s) 122 (7.02%) 234 (-9.65% ) 1188 (14.12%) 3003 (-0.23%) 3143 (0.26% ) 4842 (-0.19%) 4603 (-0.04%)
PPW 0.0576(1.59%) 0.0979(6.07% ) 0.111(-6.49%) 0.1796(2.51% ) 0.1971(1.70% ) 0.3216(0.34% ) 0.3051(-0.42%)
============= =================== ============== ================ ============= =============== ============== =============== ===============
2.Dbench
(Energy less is better, Throughput more is better,
PPW--Performance per Watt more is better)
============= =================== ============== =============== ============== =============== ============== =============== ===============
Trans Delay Dbench governor:schedutil, 3-iterations average
============= =================== ============== =============== ============== =============== ============== =============== ===============
1000us Clients 1 2 4 8 12 16 32
Energy/Joules 4890 3779 3567 5157 5611 6500 8163
Throughput/(MB/s) 327 167 220 577 775 938 1397
PPW 0.0668 0.0441 0.0616 0.1118 0.1381 0.1443 0.1711
600us Clients 1 2 4 8 12 16 32
Energy/Joules 4915 (0.51%) 4912 (29.98%) 3506 (-1.71%) 4907 (-4.85% ) 5011 (-10.69%) 5672 (-12.74%) 8141 (-0.27%)
Throughput/(MB/s) 348 (6.42%) 284 (70.06%) 220 (0.00% ) 518 (-10.23%) 712 (-8.13% ) 854 (-8.96% ) 1475 (5.58% )
PPW 0.0708(5.99%) 0.0578(31.07%) 0.0627(1.79% ) 0.1055(-5.64% ) 0.142(2.82% ) 0.1505(4.30% ) 0.1811(5.84% )
============= =================== ============== =============== ============== =============== ============== =============== ===============
3.Hackbench(less time is better)
============= =========================== ==========================
hackbench governor:schedutil
============= =========================== ==========================
Trans Delay Process Mode Ave time(s) Thread Mode Ave time(s)
1000us 14.484 14.484
600us 14.418(-0.46%) 15.41(+6.39%)
============= =========================== ==========================
4.Perf_sched_bench(less time is better)
============= =================== ============== ============== ============== =============== =============== =============
Trans Delay perf_sched_bench governor:schedutil
============= =================== ============== ============== ============== =============== =============== =============
1000us Groups 1 2 4 8 12 24
AveTime(s) 1.64 2.851 5.878 11.636 16.093 26.395
600us Groups 1 2 4 8 12 24
AveTime(s) 1.69(3.05%) 2.845(-0.21%) 5.843(-0.60%) 11.576(-0.52%) 16.092(-0.01%) 26.32(-0.28%)
============= ================== ============== ============== ============== =============== =============== ==============
5.Sysbench(higher is better)
============= ================== ============== ================= ============== ================ =============== =================
Sysbench governor:schedutil
============= ================== ============== ================= ============== ================ =============== =================
1000us Thread 1 2 4 8 12 24
Ave events 6020.98 12273.39 24119.82 46171.57 47074.37 47831.72
600us Thread 1 2 4 8 12 24
Ave events 6154.82(2.22%) 12271.63(-0.01%) 24392.5(1.13%) 46117.64(-0.12%) 46852.19(-0.47%) 47678.92(-0.32%)
============= ================== ============== ================= ============== ================ =============== =================
In conclusion, a shorter transition delay
of cpu clock will make a quite positive effect to improve PPW
on Dbench test, in the meanwhile, keep stable performance
on Tbench, Hackbench, Perf_sched_bench and Sysbench.
Signed-off-by: Xiaojian Du <Xiaojian.Du@amd.com>
Reviewed-by: Perry Yuan <perry.yuan@amd.com>
Acked-by: Mario Limonciello <mario.limonciello@amd.com>
|
History
|
|
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.