Arch Linux

euromatlox

Member

Registered: 2017-02-10

Posts: 110

[Solved] Slow performance with latest kernels (4.9.8-1)

The slow performance was detected with kernel 4.9.8-1 and two very latest kernels before that.

I am using Xfce Desktop Environment, version 4.12.
My system board is Asus P5W DH Deluxe, 4Gb memory, and display adapter is NVidia 8500GT 256mb.

Because of this 'slowness' I did some maintenance and removed some unneeded packages (mostly Gnome related), but it did not help.

Modifying (optimizing) some web browser settings helped a little (but only web browsing).

But I have found out that adding the following boot parameters partially solve this problem:

pcie_port_pm=0
acpi_osi=Linux

=> my kernel load line (in menu.lst file) looks like this:

kernel /vmlinuz-linux root=/dev/sda5 ro vga=792 pcie_port_pm=0 acpi_osi=Linux init=/usr/lib/systemd/systemd

Interested to hear if someone has similar problems and what has been changed in the kernel.

Last edited by euromatlox (2017-02-11 10:33:38)

graysky

Wiki Maintainer

From: :wq

Registered: 2008-12-01

Posts: 10,597

Website

Re: [Solved] Slow performance with latest kernels (4.9.8-1)

You need a quantitative measure of slow performance.  Anything else is just perception in my opinion.

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CPU-optimized Linux-ck packages @ Repo-ck  • AUR packages • Zsh and other configs

dkaylor

Member

Registered: 2015-04-10

Posts: 7

Re: [Solved] Slow performance with latest kernels (4.9.8-1)

@euromatlox - I noticed when going through kernel config for 4.9 kernels that "schedutil" is now the default cpufreq governor. Was "ondemand" previously, might be worth changing the governor and see if you notice much difference. I have tried both and haven't noticed much, but haven't tried any benchmarks.

euromatlox

Member

Registered: 2017-02-10

Posts: 110

Re: [Solved] Slow performance with latest kernels (4.9.8-1)

Thanks dkaylor. I figured it out.

Somehow I had p4-clockmod enabled in my system instead of acpi-cpufreq.
So I removed p4-clockmod and enabled acpi-cpufreq (and rebooted).

Now it seems than no governor is active, but system works smooth as before.
When p4-clockmod was enabled, also that cpufreq_ondemand was active, and system was much slower.

# cpupower frequency-info
analyzing CPU 0:
  no or unknown cpufreq driver is active on this CPU
  CPUs which run at the same hardware frequency: Not Available
  CPUs which need to have their frequency coordinated by software: Not Available
  maximum transition latency:  Cannot determine or is not supported.
  hardware limits: Not Available
  available cpufreq governors: Not Available
  Unable to determine current policy
  current CPU frequency: Unable to call hardware
  current CPU frequency:  Unable to call to kernel
  boost state support:
    Supported: no
    Active: no