Re: suspend, power save or saving, hibernate mode in Indpiron 5160
H. S. wrote:
> I am trying to make some sense of these modes in Dell Inspiron 5160. I
> am using ACPI (with acpid) and it seems to regulate the fan(fan is
> really quit often) and tells me about the battery status. But I am not
> sure if the suspend/hibernate/power saving modes work.
> 1) how do I test for these?
APM should work because it is a BIOS function. But ACPI moves all of
that functionality into the kernel. At the moment the stock linux
kernel does not work. (Depending upon how gracious you are in
defining work.) There are a set patches to create this functionality.
> 2) Second, do I need these option for these modes to work(they are
> commented out in my current kernel.)?
Those are the original config variables to enable suspending to disk.
That used to work in older kernels. But the code has not aged well
and most find it non-functional now with newer kernels. Therefore the
software suspend 2 project was started to correct those issues.
> 3) This website gives some different options
> http://softwaresuspend.berlios.de/Software-suspend-2.html#ss2.1 :
> What is this all about?
This is the new project which has replaced the older one. These are
being merged into the kernel now. But it is not there quite yet. So
at the moment to get these you need to apply the swsusp2 patches. If
you have a newer ACPI laptop then you will want to do this. Or wait
until it merges into the official kernel. But you won't be able to
suspend until you do. (I could not get the older PM version to
function on my laptop. But the newer swsusp2 patches are working well
> 4) Whis is better, apm or acpi?
APM is the older method supported by the BIOS. ACPI is the newer
method that is handled by the operating system. The APM version
generally just worked. The ACPI version has the potential to work
better provided the OS has the code to handle it. But it does not
really matter which is better. Newer laptops do not provide the APM
functionality and so regardless you will need to deal with ACPI if you
have one of those. I was forced into ACPI for my new laptop.
> 5) Does the closing the lid and making the laptop go to
> suspend/hibernate work?
Not unless you had an event script to activate suspend upon the lid
closing event. See the 'acpid' for one way to handle this.