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goxepamurefu

Member

Registered: 2016-05-28

Posts: 1

[Solved] SSD: Prevent APM change on power cord plug/unplug

I'am using a laptop with ssd.
No power management like xfce4-power-manager, laptop-mode-tools or tlp installed. The ideapad_laptop module is already blacklistet.
My problem: On every unplug of the power cord the APM level of the ssd changes from 254 to 128 wich leads to slow transfer rates write about 50MB/s. When I connect the power cord the APM level of the ssd switches back to 254 with tranfer rates write about 230MB/s (SATA 2).
Question: What causes this APM change? How can I stop this behaviour and make the 254 APM setting persistant as this behaviour seems to have no benefits on a ssd.

Last edited by goxepamurefu (2016-06-01 12:05:19)

R00KIE

Forum Fellow

From: Between a computer and a chair

Registered: 2008-09-14

Posts: 4,734

Re: [Solved] SSD: Prevent APM change on power cord plug/unplug

I would double check that no power management software or daemon is running. Another thing to check is bios/uefi settings, as there might be some option for power saving when on battery that could be doing that.

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R00KIE
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