Laptop ACPI question

[Markie]

----- Original Message ----- 
From: "Kevin Oberman" <oberman at es.net>
To: "Markie" <mark.cullen at dsl.pipex.com>
Cc: <freebsd-mobile at freebsd.org>
Sent: Sunday, May 02, 2004 11:14 PM
Subject: Re: Laptop ACPI question


| > From: "Markie" <mark.cullen at dsl.pipex.com>
| > Date: Sat, 1 May 2004 22:28:55 +0100
| >
| >
| > ----- Original Message ----- 
| > From: "Kevin Oberman" <oberman at es.net>
| > To: "Markie" <mark.cullen at dsl.pipex.com>
| > Cc: <freebsd-mobile at freebsd.org>
| > Sent: Saturday, May 01, 2004 10:05 PM
| > Subject: Re: Laptop ACPI question
| >
| >
| > | > From: "Markie" <mark.cullen at dsl.pipex.com>
| > | > Date: Sat, 1 May 2004 21:29:56 +0100
| > | > Sender: owner-freebsd-mobile at freebsd.org
| > | >
| > | > Hello,
| > | >
| > | > Just a quick question... would having ACPI working on a laptop
increase
| > | > battery life at all? I just left it sat idle without ACPI and it
got to
| > an
| > | > hour and 30 minutes... I went to start xchat and it just switched
off
| > | > straight away after it started loading :o) if I leave it doing `cat
| > | > /dev/random > /dev/null` it only lasts 45 minutes :o(
| > | >
| > | > I am just wondering if it's a naffed battery... or... there's
something
| > a
| > | > bit wrong with the laptop or... I just need ACPI? I don't really
know
| > what
| > | > ACPI does, so.... :o)
| > |
| > | Actually, ACPI will greatly improve battery life soon, but not yet.
The
| > | bits and pieces are being fed into CURRENT and I suspect that
SpeedStep
| > | support will be coming soon.
| > | In the meantime, you can use sysctls to manually adjust CPU
performance
| > | to enhance battery life.
| > |
| > | Look at:
| > | hw.acpi.cpu.throttle_max: 8
| > | hw.acpi.cpu.throttle_state: 8
| > | hw.acpi.cpu.cx_supported: C1/0 C2/1 C3/85
| > | hw.acpi.cpu.cx_lowest: 0
| > | hw.acpi.cpu.cx_history: 1453705/0 0/0 0/0
| > |
| > | Reducing the hw.acpi.cpu.throttle_state will increase battery life by
| > | effectively reducing CPU speed. The reduction is linear and a setting
of
| > | 1 makes my system crawl.
| > |
| > | Setting hw.acpi.cpu.cx_lowest will reduce the responsiveness of P4-M
or
| > | Centrino system by putting the system in a "deeper sleep" than just
| > | halting the CPU. The cost is that it takes longer for the system to
| > | start processing again. Its effect can appear as jerkiness in some
| > | operations. It may be set to as many values (higher is slower) as are
| > | listed in cx_history. (In the example, there are three, 0, 1, and 2
| > | available.)  Depending on hardware connected, some levels may not be
| > | available. On my laptop, 2 is not available if the USB driver is
loaded.
| > |
| >
| > Thanks for both your replies! I am not too sure I have speed step or
| > anything. It's a fairly old CPU, a mobile celeron 800MHz, 100MHz FSB
| > (anyone know anything about these at all? are they not that good? seems
| > nice and quick to me). I guess I am pretty buggered then. There's not
alot
| > of info I can find about the laptop either. In any case, it wouldn't
boot
| > with ACPI enabled anyway... so I think I am just double buggered :o)
|
| Make sure that your BIOS is te latest available. That can make a huge
| difference. The CPU is not the critical issue; it's the BIOS
| support. Older systems may simply not run well with ACPI and APM is the
| best way to go on these systems. (Have you tried APM?)

Ahh! BIOS Update :o) I will get on that one right away! Hopefully it may
fix my ACPI issues. On their site they said it was required for installing
Windows XP so it must do something!

According to the version numbers it is one version higher, I have R01-A1s
and I just downloaded R01-A1t. I sure hope it fixes some things!
Unfortuantly there's no change log

|
| > All I know is some site said that the battery was supposed to last 2
hours
| > ish, which would be cool. No doubt this was taken with the laptop
sitting
| > totally idle though.
|
| Battery benchmarking is tricky and highly variable. And, as batteries
| age, they go downhill. Try the command 'acpiconf -i 0' to get a lot of
| detailed battery information on current. I think it works on 5.2.1, but
| may have to run as root. I may tell you things like how much of a
| charge the battery is taking and the type and manufacturer.

I figured it would be hard. I am looking at external batteries if ACPI
doesn't help at all, quite expensive though... but I love computers so I
will need quite a bit of battery life :o)

I don't think I will be able to run that command without ACPI will I?

|
| > I will have to try Linux or Windows if I can't get FreeBSD ACPI working
and
| > see if it gets me any more battery life I guess! Such a shame, it
doesn't
| > seem that bad of a laptop for what I want... but if I have to use it on
| > mains it's not as useful as it could be!
|
| Most ACPI code is shared by Linux and FreeBSD as it is based closely on
| the Intel supplied sources. It is possible that Linux support for
| control of different parts of the ACPI is more advanced. but I suspect
| it's pretty close.

I see, i'll stick to just wasting some time trying Windows then ;o)

|
| Since every vendor makes sure that their Windows code plays well with
| their hardware, it's unlikely that open source software will ever quite
| catch up with it, but it is rapidly closing the gap. It's just that,
| until a few more pieces are in place, it's not obvious.

Yeah, I hear ACPI and all the funky power saving stuff is coming along
quite nicely :o)

Thanks for all your informative replies, that goes to everyone :o)

*bios update time*

| -- 
| R. Kevin Oberman, Network Engineer
| Energy Sciences Network (ESnet)
| Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
| E-mail: oberman at es.net Phone: +1 510 486-8634