OLPC:News

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You can subscribe to the OLPC community-news mailing list by visiting the laptop.org mailman site.

Laptop News 2007-10-06

1. Addis Ababa: Matt Keller and David Cavallo ran a learning workshop for leaders from the Ethiopian Ministry of Capacity Building (MoCB), school principals, teachers, university support people, the team from GTZ, and local software people. The GTZ team led by Thomas Rolf is doing an incredible job coordinating with MoCB in implementing the work and guiding the project.

2. Gamepad button: when “left” was pushed on the game-pad controller (on the left side of the bezel) in B3/B4/C machines, the response was usually “down.” A small change in tooling proposed and executed by Quanta has fixed this; “left” will be working in the mass-production units.

3. Trial 3: We are very close to our Trial-3 build; several key bug fixes are underway and we should close out development very soon. Development for first release (primarily bug fixes) is underway (See [1]). We encourage you to try the current build. Community feedback from the early use of recent builds helps us uncover bugs; for example, a Journal/JFFS2 bug that we are resolving now.

4. Schedule: We had a number of meetings this week on the feature set (and bugs) for first deployment, including a review meeting with the Collabra team at our Cambridge (MA) offices. The feature-freeze date for First Deployment is October 16; the code-freeze date is November 2 (See [2]).

5. Testing: Alex Latham tested many areas of the latest releases this week in order to find regressions and get through verification of recently fixed bugs. His focus was on mime types—getting the right activities to be available for opening files—and “real” activation testing on firmware-protected laptops. Alex also tested our new Amharic keyboard; Watch and Listen Version 8; human-readable filenames in the Journal; the upgrade process from Build 542 to our more recent builds; and Record playback. Yani Galanis tested various configurations related to network management: link-local mesh and school-server mesh. He is documenting everything we know about routing tables, Gabble and Salut in regard to how they interact with our various network configurations.

6. Sugar and activities: Simon Schamijer fixed a bug that was preventing the display of “myself” in the Friends View. Simon modified the behavior of the network icons (AP and MeshDevice) in the Mesh View; they no longer blink when activated—instead, the border circle turns from colored to white. This is in order to save power since blinking graphics require the system to wake up and use power unnecessarily. Simon also made some adjustments to the behavior of the Browse Activity: it now starts with the Browse Tab open; the warning page for about:config has been disabled; browse history has been limited to 50 entries; the history entries are displayed in pages of 15 entries each for both the back and forward buttons. Marco Pesenti Gritti tracked down/fixed a few issues with the media players and mime associations. Thanks to the efforts of the team at NATE-LSI, Universidade de São Paulo, Paint now resumes from the Journal. Erik Blankinship and Bakhtiar Mikhak have re- enabled picture deletion in the Record Activity.

7. Journal and datastore: Tomeu Vizoso profiled, studied and improved the performance of the datastore with Marco and Ben Saller. They fixed the worst bottlenecks in both the datastore and Journal. Preview images had been incorrectly stored, causing slow updates and retrieval of results, high memory usage, and the waste of flash space. Updates were being flushed to the index too often, causing fragmentation in the jffs2 file system to the point that, at startup, the garbage-collector thread took much of the CPU—enough for some services to remain stuck until they were restarted. Improvements were made to the performance and memory consumption of the datastore’s use of Xapian (the search engine). After further testing we hoping to incorporate the changes into Trial-3, as they represent a significant performance improvement.

Along with Dave Woodhouse, they tracked down the “white journal” problem (trac #3978). David looked at the associated JFFS2 problem; initial diagnosis is fairly much as expected; one of the fixes is to change the criteria for when garbage collection (GC) is triggered. We had been running GC only when we actually need the space, but we should probably do it when we have a lot of obsolete nodes, even if we don't yet need the space. Simon Schamijer corrected the way the Journal displays bundles by exploiting .activity information (trac #3757). Tomeu also worked on a problem regarding the recreation of the datastore index on mount failure of removable devices (trac #3180). He also fixed tags field in the detail view (trac #3180) and refreshed the toolbar filters when an entry is created (trac #3790).

8. Security: Ivan Krstić reports that the laptop tracking application (named “Bentham”) is finished. Michael Stone—along with Marco and Tomeu—has been actively engaged in a discussion on the Sugar mailing list in regard to user interaction for file open and/or Journal access (See trac #2328). The discussion raises concerns about low-level APIs and semantics and is further documented in trac #3801 (“Rainbow, Sugar, and the Datastore need to integrate to isolate Activities from the Datastore”). Michael also worked with Andres Salomon and Herbert Poetzl to test and fix the available vserver patches. All available patches have been integrated into our kernel and will soon appear in builds. (This work should allow us to close trac #3924.) Andres also prepared new kconfig patches for upstream (something that he had put off for a few weeks while working on power-management stuff). He is finishing them up and get them upstream ASAP.

9. Suspend/resume: How many suspend/resume cycles does your laptop make before crashing? At OLPC, we strive for millions of cycles, and have been making progress toward that goal. Around one-month ago we realized that our laptop was having hardware problems related to suspending and resuming. These problems were significant when a laptop was woken from suspend by the arrival of a network packet addressed to it.

We quickly identified the most significant causes of crashes (waiting until a clock settled, and a precipitous turning on of various parts of the laptop), and have slowly worked on identifying and fixing the remaining problems. The difficulty lies in the infrequent nature of the remaining problems. Obtaining meaningful test results can take several days.

In order to correct this, we have built a testbed for long-term testing of suspend/resume problems. Presently, around twenty laptops are in the testbed, continually going into suspend and then resuming to respond to a network packet arriving every second. The serial console of the main processor in each laptop (and in some cases, the serial console of the embedded power controller) are continually logged so that we can identify the cause of a crash.

John Watlington wants to thank the entire OLPC team for their help with this problem. Everyone has pitched in, from Yani Galanis helping to modify the laptops, Alex Latham, Chris Ball, and Danny Clark working on setting up testbeds, Richard Smith providing crucial pieces of firmware (while at the end of a 48 Kbps phone line in Arkansas), Joshua Seals getting tools, to Andres Salomon and Mitch Bradley working on the DCON workaround. Our colleagues at Quanta have also been working hard to fix and test these problems.

10. Build System: Chris Ball worked on automation improvements to our “pilgrim” script for creating builds, with Scott Ananian and Michael Stone Scott Ananian fixed the upgrade server on updates.laptop.org to install new builds on demand. The three of them discussed and designed refactorings of our current build system and implemented an hourly build of two new build branches, “Joyride” (our new “unstable” branch) and “Meshtest” (automatically installed on our mesh testbed, which auto-runs mesh network tests). To add a package to Joyride, place an RPM in ~/public_rpms/joyride/ in your account on dev.laptop.org. It will automatically be included in the next hourly build (See [3]). It may take an extra hour for the presence of a new ~/public_rpms directory to be registered.

11. Updates: Scott installed sample Debian and Debian-big “updates” on updates.laptop.org as a proof-of-concept. Scott also improved persistence of internationalization settings on upgrade. Note that there is an olpc-update program in our newer builds can now update a system quickly without reimaging or the cumbersome USB update procedure. This makes it very easy to update to the current build (or install other builds entirely).

12. Pretty boot: Scott landed improved “pretty boot,”visible when booting in “secure” mode. Scott also added a UL safety warning screen to the shutdown sequence.

13. X Window System: First the good news: we may have found a smoking gun for the “jumpy mouse” bug. There seems to be a locking bug in the kernel. Andres has not had time to work with Bernardo Innocenti to resolve them yet, but we are confident that we are on the right path. Also, X Server 1.4 is ready for prime time! Input autoconfiguration works. Bernie has a few questions for the author of evdev, but it is good enough for general usage. He is packaging up things for testers. And then the bad news: Ethiopic has regressed somehow. But there is a fix on the horizon: it should work with the latest version of glibc (2.6.90-17).

14. Firmware: Dave Woodhouse helped Mitch Bradley to find and fix an ECC correction bug in OpenFirmware, which is what caused Nicholas to bring a non-booting machine back from a demonstration. Dave has also set up a test cycling DCON power on and off repeatedly, with no interesting results so far.

Mitch released Q2C28 firmware, the test candidate for mass production. It supports security (and pretty boot), and includes a UL safety warning screen behind a button. He also designed the secure NAND filesystem update; implemented the firmware support for it and Linux tools to create the images.

Scott worked with Mitch on firmware security: a secure USB upgrade mechanism for unactivated machines and a key deprecation mechanism.

Richard Smith released all his EC code patches to Quanta. Quanta is still working on some changes to the NiMH charging code with GoldPeak. Richard merged in their pre-release and re-submitted his patches.

15. Core activities: There has been a discussion on the devel list about the criteria for inclusion of core activities on the laptop. We’d like to broaden the discussion. Some proposed “Criteria for Inclusion”:

A. Epistemological impact—to what degree does this activity positively impact learning? (This is of course the most important criteria.)

B. Fun—is it fun? engaging?

C. Quality—is the activity sufficiently robust in its implementation that it will not compromise the integrity or supportability of the system? Is the overall quality of the implementation adequate to meet our standards? Can the community be engaged in the process of testing and “certifying” and maintaining the activity?

D.Sugarized—to what extent has the activity been integrated into Sugar, including UI, Journal, security, internationalization, etc.? Does the activity require the folding in of additional libraries and resources? (This has impact on robustness—positive and negative—support, bloat, and the overall usability, aesthetics, and perception of quality of the machine.)

E. FOSS—is the activity and all of its dependencies free and open?

F. Extensible—is the activity something the community can extend? Does it span multiple needs? (And does it have—or the potential of having—an upstream community of support?)

G. Uniqueness—does the activity add a unique feature to the core?

H. Expectations—does the activity meet the expectations of (children, teachers, parents, G1G1 audience, etc.)?

I. Discoverable—is the core activity discoverable? (This is not to say that it shouldn't be hard work to fully exploit the power of an activity, but it should have a low barrier to entry.)

More News

Laptop News is archived at Laptop News. Also on community-news.

You can subscribe to the OLPC community-news mailing list by visiting the laptop.org mailman site.

Press requests: please send email to press@racepointgroup.com

Milestones

Latest milestones:

Nov. 2007 Mass Production has started.
July. 2007 One Laptop per Child Announces Final Beta Version of its Revolutionary XO Laptop.
Apr. 2007 First pre-B3 machines built.
Mar. 2007 First mesh network deployment.
Feb. 2007 B2-test machines become available and are shipped to developers and the launch countries.
Jan. 2007 Rwanda announced its participation in the project.

All milestones can be found here.


Press

You can subscribe to the OLPC community-news mailing list by visiting the laptop.org mailman site.

  This page is monitored by the OLPC team.
   HowTo [ID# 68780]  +/-  

You can subscribe to the OLPC community-news mailing list by visiting the laptop.org mailman site.

Laptop News 2007-10-06

1. Addis Ababa: Matt Keller and David Cavallo ran a learning workshop for leaders from the Ethiopian Ministry of Capacity Building (MoCB), school principals, teachers, university support people, the team from GTZ, and local software people. The GTZ team led by Thomas Rolf is doing an incredible job coordinating with MoCB in implementing the work and guiding the project.

2. Gamepad button: when “left” was pushed on the game-pad controller (on the left side of the bezel) in B3/B4/C machines, the response was usually “down.” A small change in tooling proposed and executed by Quanta has fixed this; “left” will be working in the mass-production units.

3. Trial 3: We are very close to our Trial-3 build; several key bug fixes are underway and we should close out development very soon. Development for first release (primarily bug fixes) is underway (See [4]). We encourage you to try the current build. Community feedback from the early use of recent builds helps us uncover bugs; for example, a Journal/JFFS2 bug that we are resolving now.

4. Schedule: We had a number of meetings this week on the feature set (and bugs) for first deployment, including a review meeting with the Collabra team at our Cambridge (MA) offices. The feature-freeze date for First Deployment is October 16; the code-freeze date is November 2 (See [5]).

5. Testing: Alex Latham tested many areas of the latest releases this week in order to find regressions and get through verification of recently fixed bugs. His focus was on mime types—getting the right activities to be available for opening files—and “real” activation testing on firmware-protected laptops. Alex also tested our new Amharic keyboard; Watch and Listen Version 8; human-readable filenames in the Journal; the upgrade process from Build 542 to our more recent builds; and Record playback. Yani Galanis tested various configurations related to network management: link-local mesh and school-server mesh. He is documenting everything we know about routing tables, Gabble and Salut in regard to how they interact with our various network configurations.

6. Sugar and activities: Simon Schamijer fixed a bug that was preventing the display of “myself” in the Friends View. Simon modified the behavior of the network icons (AP and MeshDevice) in the Mesh View; they no longer blink when activated—instead, the border circle turns from colored to white. This is in order to save power since blinking graphics require the system to wake up and use power unnecessarily. Simon also made some adjustments to the behavior of the Browse Activity: it now starts with the Browse Tab open; the warning page for about:config has been disabled; browse history has been limited to 50 entries; the history entries are displayed in pages of 15 entries each for both the back and forward buttons. Marco Pesenti Gritti tracked down/fixed a few issues with the media players and mime associations. Thanks to the efforts of the team at NATE-LSI, Universidade de São Paulo, Paint now resumes from the Journal. Erik Blankinship and Bakhtiar Mikhak have re- enabled picture deletion in the Record Activity.

7. Journal and datastore: Tomeu Vizoso profiled, studied and improved the performance of the datastore with Marco and Ben Saller. They fixed the worst bottlenecks in both the datastore and Journal. Preview images had been incorrectly stored, causing slow updates and retrieval of results, high memory usage, and the waste of flash space. Updates were being flushed to the index too often, causing fragmentation in the jffs2 file system to the point that, at startup, the garbage-collector thread took much of the CPU—enough for some services to remain stuck until they were restarted. Improvements were made to the performance and memory consumption of the datastore’s use of Xapian (the search engine). After further testing we hoping to incorporate the changes into Trial-3, as they represent a significant performance improvement.

Along with Dave Woodhouse, they tracked down the “white journal” problem (trac #3978). David looked at the associated JFFS2 problem; initial diagnosis is fairly much as expected; one of the fixes is to change the criteria for when garbage collection (GC) is triggered. We had been running GC only when we actually need the space, but we should probably do it when we have a lot of obsolete nodes, even if we don't yet need the space. Simon Schamijer corrected the way the Journal displays bundles by exploiting .activity information (trac #3757). Tomeu also worked on a problem regarding the recreation of the datastore index on mount failure of removable devices (trac #3180). He also fixed tags field in the detail view (trac #3180) and refreshed the toolbar filters when an entry is created (trac #3790).

8. Security: Ivan Krstić reports that the laptop tracking application (named “Bentham”) is finished. Michael Stone—along with Marco and Tomeu—has been actively engaged in a discussion on the Sugar mailing list in regard to user interaction for file open and/or Journal access (See trac #2328). The discussion raises concerns about low-level APIs and semantics and is further documented in trac #3801 (“Rainbow, Sugar, and the Datastore need to integrate to isolate Activities from the Datastore”). Michael also worked with Andres Salomon and Herbert Poetzl to test and fix the available vserver patches. All available patches have been integrated into our kernel and will soon appear in builds. (This work should allow us to close trac #3924.) Andres also prepared new kconfig patches for upstream (something that he had put off for a few weeks while working on power-management stuff). He is finishing them up and get them upstream ASAP.

9. Suspend/resume: How many suspend/resume cycles does your laptop make before crashing? At OLPC, we strive for millions of cycles, and have been making progress toward that goal. Around one-month ago we realized that our laptop was having hardware problems related to suspending and resuming. These problems were significant when a laptop was woken from suspend by the arrival of a network packet addressed to it.

We quickly identified the most significant causes of crashes (waiting until a clock settled, and a precipitous turning on of various parts of the laptop), and have slowly worked on identifying and fixing the remaining problems. The difficulty lies in the infrequent nature of the remaining problems. Obtaining meaningful test results can take several days.

In order to correct this, we have built a testbed for long-term testing of suspend/resume problems. Presently, around twenty laptops are in the testbed, continually going into suspend and then resuming to respond to a network packet arriving every second. The serial console of the main processor in each laptop (and in some cases, the serial console of the embedded power controller) are continually logged so that we can identify the cause of a crash.

John Watlington wants to thank the entire OLPC team for their help with this problem. Everyone has pitched in, from Yani Galanis helping to modify the laptops, Alex Latham, Chris Ball, and Danny Clark working on setting up testbeds, Richard Smith providing crucial pieces of firmware (while at the end of a 48 Kbps phone line in Arkansas), Joshua Seals getting tools, to Andres Salomon and Mitch Bradley working on the DCON workaround. Our colleagues at Quanta have also been working hard to fix and test these problems.

10. Build System: Chris Ball worked on automation improvements to our “pilgrim” script for creating builds, with Scott Ananian and Michael Stone Scott Ananian fixed the upgrade server on updates.laptop.org to install new builds on demand. The three of them discussed and designed refactorings of our current build system and implemented an hourly build of two new build branches, “Joyride” (our new “unstable” branch) and “Meshtest” (automatically installed on our mesh testbed, which auto-runs mesh network tests). To add a package to Joyride, place an RPM in ~/public_rpms/joyride/ in your account on dev.laptop.org. It will automatically be included in the next hourly build (See [6]). It may take an extra hour for the presence of a new ~/public_rpms directory to be registered.

11. Updates: Scott installed sample Debian and Debian-big “updates” on updates.laptop.org as a proof-of-concept. Scott also improved persistence of internationalization settings on upgrade. Note that there is an olpc-update program in our newer builds can now update a system quickly without reimaging or the cumbersome USB update procedure. This makes it very easy to update to the current build (or install other builds entirely).

12. Pretty boot: Scott landed improved “pretty boot,”visible when booting in “secure” mode. Scott also added a UL safety warning screen to the shutdown sequence.

13. X Window System: First the good news: we may have found a smoking gun for the “jumpy mouse” bug. There seems to be a locking bug in the kernel. Andres has not had time to work with Bernardo Innocenti to resolve them yet, but we are confident that we are on the right path. Also, X Server 1.4 is ready for prime time! Input autoconfiguration works. Bernie has a few questions for the author of evdev, but it is good enough for general usage. He is packaging up things for testers. And then the bad news: Ethiopic has regressed somehow. But there is a fix on the horizon: it should work with the latest version of glibc (2.6.90-17).

14. Firmware: Dave Woodhouse helped Mitch Bradley to find and fix an ECC correction bug in OpenFirmware, which is what caused Nicholas to bring a non-booting machine back from a demonstration. Dave has also set up a test cycling DCON power on and off repeatedly, with no interesting results so far.

Mitch released Q2C28 firmware, the test candidate for mass production. It supports security (and pretty boot), and includes a UL safety warning screen behind a button. He also designed the secure NAND filesystem update; implemented the firmware support for it and Linux tools to create the images.

Scott worked with Mitch on firmware security: a secure USB upgrade mechanism for unactivated machines and a key deprecation mechanism.

Richard Smith released all his EC code patches to Quanta. Quanta is still working on some changes to the NiMH charging code with GoldPeak. Richard merged in their pre-release and re-submitted his patches.

15. Core activities: There has been a discussion on the devel list about the criteria for inclusion of core activities on the laptop. We’d like to broaden the discussion. Some proposed “Criteria for Inclusion”:

A. Epistemological impact—to what degree does this activity positively impact learning? (This is of course the most important criteria.)

B. Fun—is it fun? engaging?

C. Quality—is the activity sufficiently robust in its implementation that it will not compromise the integrity or supportability of the system? Is the overall quality of the implementation adequate to meet our standards? Can the community be engaged in the process of testing and “certifying” and maintaining the activity?

D.Sugarized—to what extent has the activity been integrated into Sugar, including UI, Journal, security, internationalization, etc.? Does the activity require the folding in of additional libraries and resources? (This has impact on robustness—positive and negative—support, bloat, and the overall usability, aesthetics, and perception of quality of the machine.)

E. FOSS—is the activity and all of its dependencies free and open?

F. Extensible—is the activity something the community can extend? Does it span multiple needs? (And does it have—or the potential of having—an upstream community of support?)

G. Uniqueness—does the activity add a unique feature to the core?

H. Expectations—does the activity meet the expectations of (children, teachers, parents, G1G1 audience, etc.)?

I. Discoverable—is the core activity discoverable? (This is not to say that it shouldn't be hard work to fully exploit the power of an activity, but it should have a low barrier to entry.)

More News

Laptop News is archived at Laptop News. Also on community-news.

You can subscribe to the OLPC community-news mailing list by visiting the laptop.org mailman site.

Press requests: please send email to press@racepointgroup.com

Milestones

Latest milestones:

Nov. 2007 Mass Production has started.
July. 2007 One Laptop per Child Announces Final Beta Version of its Revolutionary XO Laptop.
Apr. 2007 First pre-B3 machines built.
Mar. 2007 First mesh network deployment.
Feb. 2007 B2-test machines become available and are shipped to developers and the launch countries.
Jan. 2007 Rwanda announced its participation in the project.

All milestones can be found here.


Press

You can subscribe to the OLPC community-news mailing list by visiting the laptop.org mailman site. Template loop detected: Press More articles can be found here.

Video

Miscellaneous videos of the laptop can be found here.

More articles can be found here.

Video

Miscellaneous videos of the laptop can be found here.

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