My karma was apparently very good three weeks ago. In the last minute I secured an invitation to Linux Storage and Filesystems Workshop 2009 (LSF). This year the invitation-only workshop was hosted by the Linux Foundation on April 6-7 in San Francisco, CA. It was, as always, an intense 2 days of non-stop information exchange and decision making. I've attempted to summarize what I took away as the most interesting and important discussions of the first day. These are my opinions, and your mileage may vary.
The group of about 50 developers were nearly all present when Zach
Brown (Oracle)welcomed us and reminded folks about the ground rules of the event. Share the brownies. Wash your hands, ...just kidding. This event remains small so folks can participate and we were pretty "cozy" in the small conference room with 5 good sized round tables. First step was to turn off the projector. :)
Chris Mason and James Bottomley then did a great summary and "scoring" of promises made at LSF2008. IO stack was up first and had some good initial scores with high points for Power management, Request Based Multipath, BIO's TRIM/ERASE support, T10 DIF/DIX (complete) and FCoE (also complete). Chris Mason managed to nearly match that with 4/4 points for Barriers, BTRFS (upstream but not stable yet), IPV6 NFS, NFS RDMA.
The first problem/topic was how to cache device scanning in the kernel or how to properly export an API for device scanning. General problem is there are several methods the kernel exports info and it's very time consuming on large systems. This was followed by Async IO and Direct IO discussion led by Zach Brown (Oracle) and Jeffrey Moyer (Redhat). Zach has been the AIO maintainer "forever" and made it clear AIO was async in only a very few circumstances that happen to suit database developers.
Joe Eykholt gave a summary of "FC/SCSI Targets", how to get initiator *and* target mode support from one FC HBA at the same time. Interesting stuff. Nick Bellinger gave a concise summary of state of "LIO/iSCSI" code and the "tgt" driver.
I was interested in Tejun Heo's "libata status and issues" discussion. First we talked about the status of several patches: mvsas updates, "ATA Bus" transport class, SFF vs Native transport classes from my co-worker Gwendal Grignou, and a pile of power management patches from Kristen Accardi (Intel). Tejun then dove into the "Spurious Power Off" problem. The cause seems to be short loss of power from the PSU is causing massive FS corruption. He's documented 5 incidents so far. Additional symptoms are "clicking" sounds and START/STOP count increments (reported via SMART data). Tejun suspects the FS is issueing a FLUSH to all disks simultaneously. We further speculated that the drives might be in a low power (slower RPMpossibly) and suddenly all come to life. Currently no fix is available.
Some possible workarounds we considered:
- disable Write Cache Enable (and take a write perf hit on loads that are single threaded)
- disable power management.
He moved on to discuss ambiguities around libata/block layer data structures (e.g. hard_ vs w/o hard_ ) fields that have similar (but not the same) names.
One of the last issues was something I raised: Can we reduce the CPU utilization of the block layer? I was asking since several new flash technologies are under development and they are all capable of 200+ *thousand* IOPS. The answer was Jens Axboe was working on this already since about December 2008 had committed his initial results to his own git tree already. I just need to find the git tree and proper branch now. :)
That wraps up day one. I hope you find the information useful. If you want to read about day two, please leave a comment and if demand warrants it, I'll cover that in a future post.
Report from Day 1 of the Linux Storage and Filesystems Workshop, April 6-7, 2009
Thursday, April 30, 2009
Student Applications Open for 2009 OpenUsability Season of Usability
Wednesday, April 29, 2009
Inspired by Google Summer of Code™, the OpenUsability Season of Usability is a series of sponsored student projects to encourage students of usability, user-interface design, and interaction design to get involved with Free/Libre/Open Source Software (FLOSS) projects. Students experience the interdisciplinary and collaborative development of user interface solutions in international software projects while getting into FLOSS development.
If you are a student of design, usability, human factors, or other HCI-related field and you are interested in working on an open source project, you could work with an experienced usability mentor on a fun and interesting design project! As a bonus for working 10-15 hours a week between June 1 and August 31, there is a $1000 USD internship stipend at the end of the project.
The OpenUsability Season of Usability will be supporting 10 students to work on 10 open source projects during the June 1 - August 31 2009 season.
* Amarok
* Drupal
* Gallery
* GeneMANIA
* GNOME
* Kadu
* KOrganizer
* OLM
* SemNotes
* Ubuntu
Student applications are due May 20 2009. See http://season.openusability.org/index.php/projects for more information on the projects, student requirements, and how to apply. Questions about the projects or application process may be directed to students@openusability.org.
by Celeste Lyn Paul, Season of Usability Mentor
If you are a student of design, usability, human factors, or other HCI-related field and you are interested in working on an open source project, you could work with an experienced usability mentor on a fun and interesting design project! As a bonus for working 10-15 hours a week between June 1 and August 31, there is a $1000 USD internship stipend at the end of the project.
The OpenUsability Season of Usability will be supporting 10 students to work on 10 open source projects during the June 1 - August 31 2009 season.
* Amarok
* Drupal
* Gallery
* GeneMANIA
* GNOME
* Kadu
* KOrganizer
* OLM
* SemNotes
* Ubuntu
Student applications are due May 20 2009. See http://season.openusability.org/index.php/projects for more information on the projects, student requirements, and how to apply. Questions about the projects or application process may be directed to students@openusability.org.
by Celeste Lyn Paul, Season of Usability Mentor
Distributed Version Control for Project Hosting Users
Friday, April 24, 2009
Love our Open Source project hosting service but wish it supported distributed version control? Pine no longer! You can find full details about Mercurial support for hosted projects on the Google Code Blog.
For those of you who are Git fans, you may want to check out these articles: Develop with Git on a Google Code Project and Exporting a Git Project to Google Code.
Happy hacking!
Ed. Note: Post update to correct link.
For those of you who are Git fans, you may want to check out these articles: Develop with Git on a Google Code Project and Exporting a Git Project to Google Code.
Happy hacking!
Ed. Note: Post update to correct link.
Now Accepting Nominations for the 5th Annual Google-O'Reilly Open Source Awards
Wednesday, April 22, 2009
The Google-O'Reilly Open Source Awards are back again for 2009! These awards recognize individual contributors who have demonstrated exceptional leadership, creativity, and collaboration in the development of Open Source Software. Past recipients for 2005-2008 include Angela Byron, Andrew Tridgell, Harald Welte, Julian Seward, Karl Fogel, Martin Dougiamas, Pamela Jones and Paul Vixie.
The nomination process is open to all, so please send your nominations to osawards@oreilly.com. Nominations should include the name of the recipient, any associated projects or organizations, suggested title for the award ("Best Hacker", "Best Community Builder", etc.), and a description of why you are nominating the individual. Google and O'Reilly employees are not eligible for the awards, though we thank you if you thought of us.
Nominations close on May 22, 2009. The awards will be presented during the kickoff ceremonies for OSCON 2009. We look forward to hearing from you and having your help to honor those community members who make Open Source that much better for all of us!
Announcing Accepted Students for Google Summer of Code™ 2009
Monday, April 20, 2009
Students in 70 countries are now celebrating their acceptance in to the Google Summer of Code 2009 program! For our fifth year running the program, we've paired 1,000 students with mentors in more than 65 countries with more than 150 Free and Open Source software projects. Check out the program website for more details on each accepted student project. We're looking forward to bringing you more news about our accepted applicants in the coming weeks, but for now here's a peek at the top 5 countries for accepted student applicants: United States (212), India (101), Germany (55), Canada (44) and Brazil (43). In addition, the following countries are represented for the first time, each with 1 student: the Dominican Republic, Iceland, Luxembourg and Nigeria.
For those of you who aren't participating in the program, now is a great time to continue working on your project ideas and learning about Free and Open Source software. Each participating project is well placed to provide you with assistance in getting up to speed as a new contributor; take advantage of this opportunity to fix some bugs, hone your skills and, if you'd like, prepare for future instances of the program.
Congratulations to all students whose proposals were accepted, and many thanks to all of our applicants. The community bonding period starts today, and we'd love to hear from all of you how you plan to spend this time getting ready to start coding in six weeks. Feel free to post a comment and share your thoughts.
For those of you who aren't participating in the program, now is a great time to continue working on your project ideas and learning about Free and Open Source software. Each participating project is well placed to provide you with assistance in getting up to speed as a new contributor; take advantage of this opportunity to fix some bugs, hone your skills and, if you'd like, prepare for future instances of the program.
Congratulations to all students whose proposals were accepted, and many thanks to all of our applicants. The community bonding period starts today, and we'd love to hear from all of you how you plan to spend this time getting ready to start coding in six weeks. Feel free to post a comment and share your thoughts.