Linux on the X220

[Volker]

When I bought it, Windows 7 would idle at 6.5-7W, Linux at 10-11W. What's the situation now, a year later? Linux idles at 11-12W.

So, did you upgrade anything? Also, define idle... without WiFi and at 50% brightness my W520 idles at 12W. Fedora 15 beta with integrated only graphics.

I run powertop. I have no CPU hogs running, I have fewer than 100 wakeups per second, and powertop has no recommendations as to what else I could tweak.

Sounds like you are running the old (non-tabbed) version of powertop. The current one has a different interface with toggles instead of occasional recommendations.

[DStaal]

DStaal: You are right, I did severely misjudge your intentions. Perhaps I have not read far enough into your posts, but you were coming off as perhaps the most fickle distribution hopper in history. I apologize, I reread my comments and they seemed a bit rude; It was late and I was a bit tired.

Anyway, hopefully people newer to Linux get something out of your work. I've had fleeting interest in BSD, but would be curious to hear how that goes. It is my understanding that BSD does not usually support new hardware (which is I guess why you will be applying copious amounts of patches).

Thanks (and sorry again),
Ryan

No problem. I only mentioned what I was doing tangentially in my first post, if I mentioned it at all.

And I honestly didn't notice any rudeness.

The FreeBSD install is going to be interesting... I'm still not sure how to get what I want on a USB stick to start the process. (If I went with the standard release that wouldn't be a problem.) I will say that, according to my reading of the relevant pages, FreeBSD should support all the hardware. No issues there. The patches I want are to get v28 of ZFS in the base install; I want the de-dupe support from the start. Then I'm planning on doing something complicated: A ZFS-only install (which means I have to do all partitioning and formatting myself to start, as the installer doesn't support that yet), with the mSATA drive operating as both a cache drive and a ZIL log drive. Compression, de-dupe, and all reads and writes are funneled through the SSD transparently. It'll be fun.

---

Anyway, I just tried Fedora, starting from the Live CD. You have to stop the boot at the 'booting in X seconds' screen, and select 'basic graphics', otherwise you'll get a black screen instead of a login. This also means it doesn't guess the screen size correctly. More on that in a moment.

WiFi was detected and worked, although I got a couple notes about it crashing. (Note my upgrade here again.) The ethernet port didn't. I actually found the source for the driver (e1000e), built and installed it. Which worked fine until I hit 'install updates' and it replaced the kernel... (Since I still had the source, I just rebuilt and restarted.)

The fingerprint reader was recognized by default. It only can be used for your user password, not the root or the password safe's password, as far as I saw.

Touchpad was recognized as a touchpad, like just about everywhere else. GPointing was in the repository.

But back to the display resolution again... Even after install and the updates it still was stuck not recognizing the actual size of the display. Some web searches turned up some suggestions, but they mostly hinged on 'system-config-display', which has been removed in the current version of Fedora, with no apparent replacement. Trying to generate an X11 conf file threw an error. I'm sure eventually you could solve this problem, but it's going to take a while. In the meantime the laptop is usable, but the screen feels very small.

I also tried Sugar on a Stick, since I actually owned an OLPC at one point in the past. Again, you have to boot in basic graphics mode, and the screen resolution is wrong, but it's not as noticeable. No wired ethernet, and no hint of the fingerprint reader.

[UNIXgod]

It is my understanding that BSD does not usually support new hardware

Currently the issue is with the intel graphics driver. There is work being done on that so us FreeBSD guys can run our OS on newer intel laptops. If one wants they can use the vesa drivers in the interim.

More info here:

FreeBSD Foundation: FreeBSD Foundation Announces New Project

Like DStaal I plan on running Funtoo for now and switching to or duel booting FreeBSD down line.

I hadn't thought about the mSATA drive to be used for l2arc or zil. I'm interested in your results DStaal.

This is my first post on this forum. I am a new owner of the x220 and I love it. My main objective for owning the laptop is for software development and general hacking around.

Do you guys program? If so what languages?

[mil2]

So, did you upgrade anything?

We're talking about a year of daily system use here. I would be hard pressed to say what I did *not* upgrade in that time . In any case, five kernel releases (starting with 2.4.34), six versions of the X server, five versions of the intel display driver, five versions of mesa, two versions of KDE... Shall I keep going?

Also, define idle... without WiFi and at 50% brightness my W520 idles at 12W. Fedora 15 beta with integrated only graphics.

Wifi on with power saving. BT off. HDD with 60sec spin down. Screen brightness 7. X running with Firefox (no flash websites or some such) and a few terminal windows.

Sounds like you are running the old (non-tabbed) version of powertop. The current one has a different interface with toggles instead of occasional recommendations.

Yeah, I've tried the new one (1.97, I think) at some point. It didn't give any new insight, and consequently no improvement.

Look, Volker, I'm not trying to bash Linux here. I run it on my machines probably more than 99% of the time. I like it. However, I recognize that, like everything else, it has some shortcomings, one of which is that power management is currently not up to the level of Windows, and that in fact it's been like this for a while. So if a potential laptop buyer asks in a forum if they can expect the same battery life under Linux as under Windows, I believe that the only fair answer right now is "no", even if it pains me to say that.

[Volker]

We're talking about a year of daily system use here. I would be hard pressed to say what I did *not* upgrade in that time . In any case, five kernel releases (starting with 2.4.34), six versions of the X server, five versions of the intel display driver, five versions of mesa, two versions of KDE... Shall I keep going?

So far you haven't given us any information about what you are currently using.

Most likely there is a device that is running all the time at full throttle. Thinkpads are generally good hardware but there are a few optional choices like the Gobi WWan or the non-intel Wifi that are problematic. You can generally track these down by tracking the generated IRQs.

If your X-series thinkpad uses 12W idle then there is something not right. Did you file a bug? Most users get reasonable battery life.

[ThinkRob]

Look, Volker, I'm not trying to bash Linux here. I run it on my machines probably more than 99% of the time. I like it. However, I recognize that, like everything else, it has some shortcomings, one of which is that power management is currently not up to the level of Windows, and that in fact it's been like this for a while. So if a potential laptop buyer asks in a forum if they can expect the same battery life under Linux as under Windows, I believe that the only fair answer right now is "no", even if it pains me to say that.

I'm sorry, but I disagree with that assessment.

Yes, in some cases, with very new hardware, the drivers won't support power management as well as Windows. But that's not really the case with any of the ThinkPads that I've seen.

What I will say is that the out-of-the-box power management setup on most distributions is inferior to a lot of vendor preloads. That makes sense though: your average distro has to support a massive range of hardware, while a preload image is customized to a specific machine. Ten minutes of powertop and pm.d script fiddling though, and that difference is almost entirely gone, at least in most cases. Sometimes you'll need a different kernel config -- something that I will readily admit is not optimal -- but that's getting less and less common these days. To be fair, Windows isn't immune to this either: a clean Windows install without the Lenovo driver set will indeed be a lot less power-efficient.

That's just the way it is. Generic OS configurations may not fully exploit the features of all hardware. News at 11...

(As an aside, with regards to GPUs: I follow i915 driver development pretty closely, and while there are a few edge case power-related features that aren't supported/enabled by default, their effect is, As far as I know, minimal. FBC is a good example: it's disabled due to hardware quirks, but it only saves a fraction of a watt, and only under certain conditions. In some cases, it's difficult to say whether the closed-source Windows drivers have the same limitations.)

[mil2]

So far you haven't given us any information about what you are currently using.

True. I simply don't want to flood this thread, which is supposed to be about x220, with my experiences with an older model (x201). But since you asked: it's currently kernel 2.6.38.4, xorg-server 1.9.5, xf86-video-intel 2.15.0, mesa 7.10.2, libdrm 2.4.25, kde 4.4.5 (I'm at work and writing this from memory, so it might be minimally off).

Most likely there is a device that is running all the time at full throttle. Thinkpads are generally good hardware but there are a few optional choices like the Gobi WWan or the non-intel Wifi that are problematic.

I don't have a WWan. I have Intel 1000 Wifi (with power saving on). You are right of course that *something* must be using that extra power under Linux. You speculate that it's a single rogue device. Fair enough, though I don't know what it could be. My speculation, instead, is that it's multiple smaller things adding up. Run Thinkpad Power Manager (or whatever it's called) under Windows and scroll through the dozens of options it has to tweak the CPU, GPU, fan... For half of them, I wouldn't know where a corresponding tweak is under Linux -- it probably doesn't exist. As an example, I've recently heard on this forum that to conserve power, x220 can selectively adjust LED backlight depending on what is being shown on the screen, and that this can be controlled by software. Where do I go about adjusting this feature under Linux?

You can generally track these down by tracking the generated IRQs.

Thanks for the hint, I haven't thought about that. You mean samping /proc/interrupts to identify a line rising rapidly? I'll check at home if it shows anything interesting. Wouldn't hardware interrupts show as wakeups in powertop, though?

If your X-series thinkpad uses 12W idle then there is something not right. Did you file a bug?

As I said earlier, 12W is on the high end. It does go down to about 10-10.5W (which is still a world away from 6.5-7W under Windows).

Who exactly would I file this particular bug with, when it's so unclear which particular component is to blame? Also, see below.

Most users get reasonable battery life.

Here's the point: I don't think this is true. A number of people at my work have Thinkpads and they get battery life either comparable to mine or (more often) worse. So that's my anecdotal evidence. Where does yours come from?

And you know, "reasonable" is in the eye of the beholder. I thought my battery life was reasonable (it gives me 4+ hours with the 6-cell -- some on this forum get more like 2.5-3), until I saw how much more Windows can squeeze out of it. So my speculation is that people simply have low expectations.

Let's have a quick poll on this thread from people running Linux on their shiny new x220ies. What is the power usage that Powertop reports for you on an idle system running on battery, with reasonable settings (say, wifi on, BT off, brightness at 50%, no flashy websites in the browser). If you feel like it, also include what Lenovo tools report under Windows.

[ThinkRob]

Two side points:

1) Taking into account wakeups/s when comparing different machines seems reasonable.

2) Powertop's reported consumption -- OK, make that ACPI's reported consumption -- is not necessarily correct. (For that matter, how sure are we that the ThinkVantage tools report the right figures?)

[mil2]

Ten minutes of powertop and pm.d script fiddling though, and that difference is almost entirely gone, at least in most cases. Sometimes you'll need a different kernel config -- something that I will readily admit is not optimal -- but that's getting less and less common these days.

I've been running Linux on a daily basis for 15+ years now, so I think I can say that I know my way around, but obviously, I don't know everything. So let's get specific: are you saying that you have [seen] an x201 or x220 that, according to Powertop, idles at under 8W in Linux? If so, I would *love* to know the details such as the kernel config file and any other quirks applied in user space.

2) Powertop's reported consumption -- OK, make that ACPI's reported consumption -- is not necessarily correct. (For that matter, how sure are we that the ThinkVantage tools report the right figures?)

Very good point. I have looked into it some time ago by letting the machine run for a longer time (10-30 minutes) and sampling the reported percentage of battery remaining. What I found was that the current power use reported by *both* Powertop under Linux and ThinkVantage under Windows were off by some 15-20%, at least on my x201. So when Powertop reports 10W idle, it's actually more like 12W, and when ThinkVantage reports 6.5-7W, it's closer to 8W. Of course, the percentage of battery remaining could also be off, but these adjusted values are consistent with the nominal battery capacity and the experienced battery life. So yes, there is an error in the reported current power use values, but it is systematic, so valid comparisons between two such measurements can still be made.

[Volker]

Run Thinkpad Power Manager (or whatever it's called) under Windows and scroll through the dozens of options it has to tweak the CPU, GPU, fan... For half of them, I wouldn't know where a corresponding tweak is under Linux -- it probably doesn't exist.

Generally under /sys, e.g. /sys/devices/system/cpu/sched_mc_power_savings

As an example, I've recently heard on this forum that to conserve power, x220 can selectively adjust LED backlight depending on what is being shown on the screen, and that this can be controlled by software.

All LCD screens do that to lower the black levels in black regions. I don't think it can be controlled by software, As far as I know the LVDS interface provides no finegrained control over the backlight.