Re: Availability of XO-1.5 ATest-2 machines
On Tue, Jul 21, 2009 at 6:37 AM, Tiago Marquestiago...@gmail.com wrote: Apple quotes 7 hours of wireless productivity, not just leaving the thing idling - they deliver more than 8 hours. Notice the praise and good word of mouth. On a finished HW+SW combo after lots of testing. At very early stages they'd have said something really useful like we're trying to get more than 25 minutes battery life. And then sold about 10 units in the market. cheers, m -- martin.langh...@gmail.com mar...@laptop.org -- School Server Architect - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
On Jul 20, 2009, at 12:37 AM, Richard A. Smith wrote: Carlos Nazareno wrote: Also, what determines the dynamic clock rate from 400MHz to 1GHz? Is this auto-scaling on demand like with the old AMD Athlon64's? Does the software automatically reduce speed to 400MHz when the unit is unplugged? Dyanamic clock scaling is usefully for thermal limits only. Scaling back the clock to 400Mhz will cost you power not save it. Power savings are achieved by running as fast as you possibly can and then entering one of the lower power states where the clock is stopped. Which is why the C7-M takes this farther, and enters C4 automatically, where the external clock generator is told to stop driving the chip and the processor core power is dropped to an absolute minimum. Cheers, wad ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
On Mon, 20 Jul 2009, Richard A. Smith wrote: Carlos Nazareno wrote: If the laptop can only handle 3 hours without suspend that's fine, it's a baseline. If it could do 5 hours than it would be great. A good test would be just to use the units in ebook reader mode and try testing how long the batteries would last reading PDFs. No need for suspend/resume testing in this case. I'm going to side with Chris and support releasing numbers when we have accurate info rather than speculative information like was released for XO-1. I _still_ (last week actually) deal with deployments that think the XO uses 2 watts because of an estimated number that was used in speech on the XO-1 prior to when we had solid info. They are quite surprised when they find the XO-1 has a peak draw of 17W. the problem was that the _only_ number that was mentioned was the 'best-case' 2w number (which software has not supported using to this day) what people are asking for is the 'worst case' draw for the new system. finding better case numbers will be good, but having the worst case is very helpful. The A2 boards only booted an image with working wlan at the end of the week. We need a bit more time to make sure everything is in place for such a measurement to be accurate. yeah, you can't test the max draw of a system that you can't fully utilize. We will get some numbers soon. eagerly waiting for info. David Lang ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
Hi, To avoid further scrutiny from the media (like: http://news.cnet.com/8301-13512_3-9766574-23.html ), it would probably be better to forget the whole suspend techniques all at once. I feel like you're proposing that we avoid the problem of giving out inaccurate predictions by giving out an inaccurate prediction in the other direction -- quoting battery life times that we know we're going to be able to beat as soon as we turn on suspend/resume. My proposal is instead to stop giving out inaccurate predictions, wait a little longer, and publish real data. Thanks, - Chris. -- Chris Ball c...@laptop.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
On Mon, 20 Jul 2009, Chris Ball wrote: Hi, To avoid further scrutiny from the media (like: http://news.cnet.com/8301-13512_3-9766574-23.html ), it would probably be better to forget the whole suspend techniques all at once. I feel like you're proposing that we avoid the problem of giving out inaccurate predictions by giving out an inaccurate prediction in the other direction -- quoting battery life times that we know we're going to be able to beat as soon as we turn on suspend/resume. My proposal is instead to stop giving out inaccurate predictions, wait a little longer, and publish real data. the trouble is that there is no such thing as 'real data' with suspend/resume because the power used is so highly dependant on actual useage patterns. however a worst case 'you will always get this much time, and may get significantly more' is very repeatable and testable. David Lang ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
On Tue, Jul 21, 2009 at 4:48 AM, da...@lang.hm wrote: however a worst case 'you will always get this much time, and may get significantly more' is very repeatable and testable. Early enough in the life of the board, *all* such data is utter crap, arguing about it is a distraction and, most importantly, _people will grab the very early, absolutely craptastic numbers and repeat them for the indefinite future_ disregarding the fact that they are useless figures. That much we know. Silence, therefore, is golden. :-) cheers, m -- martin.langh...@gmail.com mar...@laptop.org -- School Server Architect - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
da...@lang.hm wrote: My proposal is instead to stop giving out inaccurate predictions, wait a little longer, and publish real data. the trouble is that there is no such thing as 'real data' with suspend/resume because the power used is so highly dependant on actual useage patterns. however a worst case 'you will always get this much time, and may get significantly more' is very repeatable and testable. The wost case will be quite disappointing as the peak power draw of this machine is higher than XO-1. I'd say how much higher but I don't yet know because we don't have the software support for turning on everything at once. (on XO-1 peak power draw was camera running full screen with a ping -f going on on WLAN) It may take a bit to discover where peak usage is on this system. I'll get an idle baseline soon. While we are on subject it would be nice to outline what usage profiles should be tested to how to automatically and repeatedly create these profiles. I've been studying the stuff listed below which outlines several different workloads and has code that will automate them if you install the apps. http://www.lesswatts.org/projects/bltk/ Unfortunately the bltk fails to run on my Ubuntu system. It seems to trip the buffer overflow detection code and gets shutdown. I've also been pondering using dogtail to automate some workloads https://fedorahosted.org/dogtail/ I'm leaning toward using dogtail to re-implement some of the suggested workloads from bltk and add some OLPC specific ones. So if anyone wanted to help then creating a couple of different automated workloads via dogtail would be very nice. This can be done on a Gen 1. I'll work on verifying that my previous power management logging stuff works on Gen 1.5. -- Richard Smith rich...@laptop.org One Laptop Per Child ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
da...@lang.hm wrote: the problem was that the _only_ number that was mentioned was the 'best-case' 2w number (which software has not supported using to this day) Not true. 8.2.1 has the ability for you go into ebook at 1W. Enable 'extreme power management' in the control panel which will disable your WLAN device. -- Richard Smith rich...@laptop.org One Laptop Per Child ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
On Mon, 20 Jul 2009, Richard A. Smith wrote: da...@lang.hm wrote: My proposal is instead to stop giving out inaccurate predictions, wait a little longer, and publish real data. the trouble is that there is no such thing as 'real data' with suspend/resume because the power used is so highly dependant on actual useage patterns. however a worst case 'you will always get this much time, and may get significantly more' is very repeatable and testable. The wost case will be quite disappointing as the peak power draw of this machine is higher than XO-1. I'd say how much higher but I don't yet know because we don't have the software support for turning on everything at once. (on XO-1 peak power draw was camera running full screen with a ping -f going on on WLAN) It may take a bit to discover where peak usage is on this system. I'll get an idle baseline soon. While we are on subject it would be nice to outline what usage profiles should be tested to how to automatically and repeatedly create these profiles. I've been studying the stuff listed below which outlines several different workloads and has code that will automate them if you install the apps. http://www.lesswatts.org/projects/bltk/ Unfortunately the bltk fails to run on my Ubuntu system. It seems to trip the buffer overflow detection code and gets shutdown. I've also been pondering using dogtail to automate some workloads https://fedorahosted.org/dogtail/ I'm leaning toward using dogtail to re-implement some of the suggested workloads from bltk and add some OLPC specific ones. So if anyone wanted to help then creating a couple of different automated workloads via dogtail would be very nice. This can be done on a Gen 1. I'll work on verifying that my previous power management logging stuff works on Gen 1.5. thank you for working to get good numbers. while I understand that worst-case numbers can be abused, I think it's much better to have 'guaranteed never to do worse than this' numbers instead of 'garanteed never to do _better_ than this' type of numbers that most vendors publish. while this does put you at a disadvantage for people that just casually look at the numbers, it will build trust with people. the biggest problem with the XO-1 numbers wasn't just the fact that they were wrong, it was the direction they were wrong in. (and the fact that the caviots that were part of the inital number announcements weren't maintained by the people re-publishing the data, including the mainstream media), so you had people planning to get long life, but ending up getting _far_ shorter lifetimes. if you set the expectation to the short side of things, then actions taken (sleep, dimming the backlight, turning off wireless, etc) are clear wins that produce longer lifetimes. I think that it would be useful to get the following numbers 1. everything running full blast 2. how much is saved by turning off each of the following components camera mic wireless backlight SD card slower CPU setting (if any) USB it would also work to define a baseline and list how much additional power some of these options use, but I don't think that is really as good as making everything subtract from the baseline after these numbers are available, then you can define workloads to try and simulate 'typical useage patterns', idle system measurements, etc (the numbers that are so squishy) re CPU speed: sometimes the cost to sleep/wake is high enough that it is better to throttle down rather than spinning idle at high speed until the timeout to go fully to sleep hits David Lang ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
On Sun, 19 Jul 2009, Chris Ball wrote: Hi Carlos, A good test would be just to use the units in ebook reader mode and try testing how long the batteries would last reading PDFs. No need for suspend/resume testing in this case. I still disagree, because ebook reading is the mode in which we use suspend the most! We suspend whenever the viewer is not actively rendering something new. I know the hardware is able to do this, but does the linux system actually to this yet? excluding the USB/SD interfaces, I believe that the XO-1 hardware is able to sleep/wake fast enough to go to sleep between keystrokes, but there isn't any software build available that actually does anything like this. I'm not aware of any sofware build that will sleep while the screen is still powered and displaying things. David Lang I agree that we should publish representative data as soon as we can, but if suspend/resume isn't included, the data aren't representative. - Chris. ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
the trouble is that there is no such thing as 'real data' with suspend/resume because the power used is so highly dependant on actual useage patterns. Can we get get representative data for a few interesting test cases? I'm thinking of something like having several people read a large document in e-book mode. If you record the timings on the keystrokes you can get an average time-per-page. Even a stopwatch might be good enough. Then just set up a system to loop through a large document at that rate until the battery runs down. You could also make a few more runs with slightly slower or faster timings. however a worst case 'you will always get this much time, and may get significantly more' is very repeatable and testable. A few more runs: Wait forever (no keystrokes), just display the same page. (best case) No wait, just display pages as fast as possible. (worst case) Then there is with/without the backlight If the numbers turn out to be crap, then we will have a nice neat pile of crap numbers that we can use to convince other people that they are crap. e-book reader is convenient because it is simple and easy for everybody to understand. What other activities have some sort of average keystroke/whatever timing that would be reasonable to measure? -- These are my opinions, not necessarily my employer's. I hate spam. ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
Hi, I know the hardware is able to do this, but does the linux system actually to this yet? Yes. I'm not aware of any sofware build that will sleep while the screen is still powered and displaying things. Every build since 8.2.0 (last October) does this, if you go to the Power control panel and turn on Automatic power management. For more power saving by turning off the wifi chip, turn on Extreme power management. For 1.5, we plan to turn this on by default, and decrease the amount of time we wait before entering suspend. - Chris. -- Chris Ball c...@laptop.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
On Mon, 20 Jul 2009, Chris Ball wrote: Hi, I know the hardware is able to do this, but does the linux system actually to this yet? Yes. I'm not aware of any sofware build that will sleep while the screen is still powered and displaying things. Every build since 8.2.0 (last October) does this, if you go to the Power control panel and turn on Automatic power management. For more power saving by turning off the wifi chip, turn on Extreme power management. my understanding from watching discussions here was that when the system went to sleep it powered down the display, because there was no way to set a timer to wake the system up a little later to then turn off the display. David Lang For 1.5, we plan to turn this on by default, and decrease the amount of time we wait before entering suspend. - Chris. ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
On Mon, Jul 20, 2009 at 6:33 PM, da...@lang.hm wrote: On Mon, 20 Jul 2009, Richard A. Smith wrote: da...@lang.hm wrote: My proposal is instead to stop giving out inaccurate predictions, wait a little longer, and publish real data. the trouble is that there is no such thing as 'real data' with suspend/resume because the power used is so highly dependant on actual useage patterns. however a worst case 'you will always get this much time, and may get significantly more' is very repeatable and testable. The wost case will be quite disappointing as the peak power draw of this machine is higher than XO-1. I'd say how much higher but I don't yet know because we don't have the software support for turning on everything at once. (on XO-1 peak power draw was camera running full screen with a ping -f going on on WLAN) It may take a bit to discover where peak usage is on this system. I'll get an idle baseline soon. While we are on subject it would be nice to outline what usage profiles should be tested to how to automatically and repeatedly create these profiles. I've been studying the stuff listed below which outlines several different workloads and has code that will automate them if you install the apps. http://www.lesswatts.org/projects/bltk/ Unfortunately the bltk fails to run on my Ubuntu system. It seems to trip the buffer overflow detection code and gets shutdown. I've also been pondering using dogtail to automate some workloads https://fedorahosted.org/dogtail/ I'm leaning toward using dogtail to re-implement some of the suggested workloads from bltk and add some OLPC specific ones. So if anyone wanted to help then creating a couple of different automated workloads via dogtail would be very nice. This can be done on a Gen 1. I'll work on verifying that my previous power management logging stuff works on Gen 1.5. thank you for working to get good numbers. while I understand that worst-case numbers can be abused, I think it's much better to have 'guaranteed never to do worse than this' numbers instead of 'garanteed never to do _better_ than this' type of numbers that most vendors publish. while this does put you at a disadvantage for people that just casually look at the numbers, it will build trust with people. the biggest problem with the XO-1 numbers wasn't just the fact that they were wrong, it was the direction they were wrong in. Precisely my point. Take, for instance, this article about the new Mac Pros: http://www.anandtech.com/mac/showdoc.aspx?i=3580 Apple quotes 7 hours of wireless productivity, not just leaving the thing idling - they deliver more than 8 hours. Notice the praise and good word of mouth. Best regards, Tiago Marques (and the fact that the caviots that were part of the inital number announcements weren't maintained by the people re-publishing the data, including the mainstream media), so you had people planning to get long life, but ending up getting _far_ shorter lifetimes. if you set the expectation to the short side of things, then actions taken (sleep, dimming the backlight, turning off wireless, etc) are clear wins that produce longer lifetimes. I think that it would be useful to get the following numbers 1. everything running full blast 2. how much is saved by turning off each of the following components camera mic wireless backlight SD card slower CPU setting (if any) USB it would also work to define a baseline and list how much additional power some of these options use, but I don't think that is really as good as making everything subtract from the baseline after these numbers are available, then you can define workloads to try and simulate 'typical useage patterns', idle system measurements, etc (the numbers that are so squishy) re CPU speed: sometimes the cost to sleep/wake is high enough that it is better to throttle down rather than spinning idle at high speed until the timeout to go fully to sleep hits David Lang ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
Hi, my understanding from watching discussions here was that when the system went to sleep it powered down the display, because there was no way to set a timer to wake the system up a little later to then turn off the display. Your understanding is incorrect, I'm afraid. We do not power down the display going into idle-suspend. - Chris. -- Chris Ball c...@laptop.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
chris wrote: Hi, my understanding from watching discussions here was that when the system went to sleep it powered down the display, because there was no way to set a timer to wake the system up a little later to then turn off the display. Your understanding is incorrect, I'm afraid. We do not power down the display going into idle-suspend. but to be clear, david's right that once the laptop's in this state there's no way to turn off the screen automatically later on -- the system must be re-awakened with user input, and then put to sleep in one of the usual (power switch or lid) ways. this is simply a limitation of current s/w. paul =- paul fox, p...@laptop.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
Paul Fox wrote: but to be clear, david's right that once the laptop's in this state there's no way to turn off the screen automatically later on -- the system must be re-awakened with user input, and then put to sleep in one of the usual (power switch or lid) ways. this is simply a limitation of current s/w. I think this is one of several good reasons why moving to cpuidle would be big win for XO-1.5 It solves the problem of managing wakeup timers, and does it in a perfectly abstracted fashion, requiring no alterations to userspace. Adding wakeup timer management to OHM sounds like a big pain, and yet another maintenance burden. --Ben signature.asc Description: OpenPGP digital signature ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
On Mon, 20 Jul 2009, Paul Fox wrote: chris wrote: Hi, my understanding from watching discussions here was that when the system went to sleep it powered down the display, because there was no way to set a timer to wake the system up a little later to then turn off the display. Your understanding is incorrect, I'm afraid. We do not power down the display going into idle-suspend. but to be clear, david's right that once the laptop's in this state there's no way to turn off the screen automatically later on -- the system must be re-awakened with user input, and then put to sleep in one of the usual (power switch or lid) ways. this is simply a limitation of current s/w. is this just a software limitation? from the prior discussion I was under the impression that there was no timer that kept running once the main board goes to sleep, so you can't program anything to wake you up later to turn more stuff off. (not a problem normally, because normal systems don't have displays that can continue to show something once the main board is off) David Lang ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
da...@lang.hm wrote: On Mon, 20 Jul 2009, Paul Fox wrote: chris wrote: Hi, my understanding from watching discussions here was that when the system went to sleep it powered down the display, because there was no way to set a timer to wake the system up a little later to then turn off the display. Your understanding is incorrect, I'm afraid. We do not power down the display going into idle-suspend. but to be clear, david's right that once the laptop's in this state there's no way to turn off the screen automatically later on -- the system must be re-awakened with user input, and then put to sleep in one of the usual (power switch or lid) ways. this is simply a limitation of current s/w. is this just a software limitation? Yes. You can use the rtcwake command to set wakeup timers for the future from userspace. However, my impression is that this is only safe if the timer is at least 2 seconds in the future at the time of suspend, due to a potential race with the EC. OHM could be modified to make use of rtcwake to, for example, wake up from sleep after 30 minutes, turn off the backlight, and suspend again. It simply hasn't been done. --Ben signature.asc Description: OpenPGP digital signature ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
da...@lang.hm wrote: On Mon, 20 Jul 2009, Paul Fox wrote: chris wrote: Hi, my understanding from watching discussions here was that when the system went to sleep it powered down the display, because there was no way to set a timer to wake the system up a little later to then turn off the display. Your understanding is incorrect, I'm afraid. We do not power down the display going into idle-suspend. but to be clear, david's right that once the laptop's in this state there's no way to turn off the screen automatically later on -- the system must be re-awakened with user input, and then put to sleep in one of the usual (power switch or lid) ways. this is simply a limitation of current s/w. is this just a software limitation? from the prior discussion I was under yes. the impression that there was no timer that kept running once the main board goes to sleep, so you can't program anything to wake you up later to turn more stuff off. (not a problem normally, because normal systems don't have displays that can continue to show something once the main board is off) rtcwake works fine, for these purposes, in later builds (post-767, because rtc wakeups weren't distinguishable in the earlier kernels). powerd uses this mechanism to accomplish screen (and system) shutdown after sleep. (olpc-powerd is the alternate power management package i wrote while i had some cough downtime from OLPC earlier this year.) paul =- paul fox, p...@laptop.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
Benjamin M. Schwartz wrote: Yes. You can use the rtcwake command to set wakeup timers for the future from userspace. However, my impression is that this is only safe if the timer is at least 2 seconds in the future at the time of suspend, due to a potential race with the EC. Not a race with the EC. Rtcwake does not go through the EC therefore the EC cannot guarantee you don't violate the minimum off time for the cpu rail. Violations result in a cpu lockup. Paul Fox's olpc-powerd does extra checking to see that an rtcwake is never scheduled such that it might violate that timing. Thats all that's required. For XO-1.5 firmware I've implemented timed EC wakeups. If that gets used for 1.5 then it's an easy backport to XO-1. It does not offer much additional advantage over using the rtc except 1s wakeups. -- Richard Smith rich...@laptop.org One Laptop Per Child ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
Hi Chris, On Sun, Jul 19, 2009 at 2:05 AM, Chris Ballc...@laptop.org wrote: Hi Carlos, Great! How's the power consumption on the XO 1.5s? Battery life under different activity conditions? I think you think we're farther along than we are -- we haven't got suspend/resume working properly yet, so can't give these numbers. You can still give us numbers without resuming and just using clock scaling can C-states. That would be a far more realistic battery life number to shout out to the world, than what happenned with the XO-1. If the laptop can only handle 3 hours without suspend that's fine, it's a baseline. If it could do 5 hours than it would be great. Best regards, Tiago Marques Also, what determines the dynamic clock rate from 400MHz to 1GHz? Is this auto-scaling on demand like with the old AMD Athlon64's? Does the software automatically reduce speed to 400MHz when the unit is unplugged? Yes, auto-scaling using acpi-cpufreq, as with most modern x86 laptops. - Chris. -- Chris Ball c...@laptop.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
You can still give us numbers without resuming and just using clock scaling can C-states. That would be a far more realistic battery life number to shout out to the world, than what happenned with the XO-1. If the laptop can only handle 3 hours without suspend that's fine, it's a baseline. If it could do 5 hours than it would be great. A good test would be just to use the units in ebook reader mode and try testing how long the batteries would last reading PDFs. No need for suspend/resume testing in this case. Regards, -Naz -- carlos nazareno http://twitter.com/object404 http://www.object404.com -- user group manager phlashers: philippine flash actionscripters adobe flash/flex/air community http://www.phlashers.com -- interactive media specialist zen graffiti studios http://www.zengraffiti.com -- if you don't like the way the world is running, then change it instead of just complaining. ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
Hi Carlos, A good test would be just to use the units in ebook reader mode and try testing how long the batteries would last reading PDFs. No need for suspend/resume testing in this case. I still disagree, because ebook reading is the mode in which we use suspend the most! We suspend whenever the viewer is not actively rendering something new. I agree that we should publish representative data as soon as we can, but if suspend/resume isn't included, the data aren't representative. - Chris. -- Chris Ball c...@laptop.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
Hi Chris, Nobody in the hardware industry publishes numbers doing the kinds of active power management techniques you use like suspend and keep the image in DCON - aside from maybe ebook readers. OLPC is up against crap stuff like the Classmate which don't have anything like that but can have a similar usage to common laptops. To avoid further scrutiny from the media (like: http://news.cnet.com/8301-13512_3-9766574-23.html ), it would probably be better to forget the whole suspend techniques all at once. Maybe it would be better to measure and quote a regular usage time, which would be +- 3 hours on an XO-1 and 8 hours on ebook mode? Best regards, Tiago Marques On Sun, Jul 19, 2009 at 11:10 PM, Chris Ballc...@laptop.org wrote: Hi Carlos, A good test would be just to use the units in ebook reader mode and try testing how long the batteries would last reading PDFs. No need for suspend/resume testing in this case. I still disagree, because ebook reading is the mode in which we use suspend the most! We suspend whenever the viewer is not actively rendering something new. I agree that we should publish representative data as soon as we can, but if suspend/resume isn't included, the data aren't representative. - Chris. -- Chris Ball c...@laptop.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
Carlos Nazareno wrote: If the laptop can only handle 3 hours without suspend that's fine, it's a baseline. If it could do 5 hours than it would be great. A good test would be just to use the units in ebook reader mode and try testing how long the batteries would last reading PDFs. No need for suspend/resume testing in this case. I'm going to side with Chris and support releasing numbers when we have accurate info rather than speculative information like was released for XO-1. I _still_ (last week actually) deal with deployments that think the XO uses 2 watts because of an estimated number that was used in speech on the XO-1 prior to when we had solid info. They are quite surprised when they find the XO-1 has a peak draw of 17W. The A2 boards only booted an image with working wlan at the end of the week. We need a bit more time to make sure everything is in place for such a measurement to be accurate. We will get some numbers soon. -- Richard Smith rich...@laptop.org One Laptop Per Child ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
Carlos Nazareno wrote: Also, what determines the dynamic clock rate from 400MHz to 1GHz? Is this auto-scaling on demand like with the old AMD Athlon64's? Does the software automatically reduce speed to 400MHz when the unit is unplugged? Dyanamic clock scaling is usefully for thermal limits only. Scaling back the clock to 400Mhz will cost you power not save it. Power savings are achieved by running as fast as you possibly can and then entering one of the lower power states where the clock is stopped. -- Richard Smith rich...@laptop.org One Laptop Per Child ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
Great! How's the power consumption on the XO 1.5s? Battery life under different activity conditions? Also, what determines the dynamic clock rate from 400MHz to 1GHz? Is this auto-scaling on demand like with the old AMD Athlon64's? Does the software automatically reduce speed to 400MHz when the unit is unplugged? Thanks for the info! -Naz -- carlos nazareno http://twitter.com/object404 http://www.object404.com -- user group manager phlashers: philippine flash actionscripters adobe flash/flex/air community http://www.phlashers.com -- interactive media specialist zen graffiti studios http://www.zengraffiti.com -- if you don't like the way the world is running, then change it instead of just complaining. ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: Availability of XO-1.5 ATest-2 machines
Hi Carlos, Great! How's the power consumption on the XO 1.5s? Battery life under different activity conditions? I think you think we're farther along than we are -- we haven't got suspend/resume working properly yet, so can't give these numbers. Also, what determines the dynamic clock rate from 400MHz to 1GHz? Is this auto-scaling on demand like with the old AMD Athlon64's? Does the software automatically reduce speed to 400MHz when the unit is unplugged? Yes, auto-scaling using acpi-cpufreq, as with most modern x86 laptops. - Chris. -- Chris Ball c...@laptop.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Availability of XO-1.5 ATest-2 machines
Hi, A small number of XO-1.5 A2 laptops has just arrived at OLPC, so it's time to start up the Contributors' Program for them! If you think you might be able to help us with hardware work, now would be an excellent time to write a mail with the following headers: To: contribut...@laptop.org Subject: XO 1.5-A2 laptop proposal letting us know what you think you could help with, mentioning any relevant work you've done in the past, and including your address and phone number for shipping. Some of the areas we'd love help with are: * Xorg driver bughunting * Kernel suspend/resume time measurement and optimization, ACPI integration, and driver work in general * Distro/packaging work that requires a machine We'll have a much larger set of beta-test machines available in the not so far future, so please don't be offended if we don't have enough machines to send you one from our small supply of alpha-test laptops. Thanks! - Chris. -- Chris Ball c...@laptop.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
