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Updated: 14 min 43 sec ago

Ben Martin: Sliding around... spinning around.

Thu, 2014-10-16 00:23
The wiring and electronics for the new omniwheel robot are coming together nicely. Having wired this up using 4 individual stepper controllers, one sees the value in commissioning a custom base board for the stepper drivers to plug into. I still have to connect an IMU to the beast, so precision strafing will (hopefully) be obtainable. The sparkfun mecanum video has the more traditional two wheels each side design, but does wobble a bit when strafing.





Apart from the current requirements the new robot is also really heavy, probably heavier than Terry. I'm still working out what battery to use to meet the high current needs of four reasonable steppers on the move.



Andrew Pollock: [life] Day 259: Kindergarten, more demos and play dates

Wed, 2014-10-15 21:25

I was pretty exhausted after yesterday, so getting out of bed this morning took some serious effort. I started the day with a chiropractic adjustment and then got stuck into doing the obligatory "pre-cleaner clean" and preparing for my third Thermomix demonstration.

The cleaners arrived and I headed off around the corner. My host thought the demo was starting at 10:30am, so I again had a bit of extra time up my sleeve.

My Group Leader, Maria, came to observe this demo, and I thought she was just going to be incognito, but to my pleasant surprise, she actually helped out with some of the washing up throughout the demo, which made it easier.

The demo went really well, and I was happy with how it went, and Maria gave me really positive feedback as well, so I was really stoked.

I got home with enough time to collapse on the couch with a book for half an hour before I biked to Kindergarten to pick up Zoe.

As we were heading out, I realised I'd left her helmet at home on her scooter. That's what I get for not putting it back on her bike trailer. So I sent her to Megan's house and biked home to pick up the helmet and headed back again. Two runs up Hawthorne Road in the afternoon heat was a good bit of exercise.

After a brief play at Megan's, we headed home, and I started dinner. For some reason, I was super organised tonight and had dinner on the table nice and early, and everything cleaned up afterwards, so we had plenty of time to go out for a babyccino before bath time and bed time, and I still managed to get Zoe to bed a little early, and I didn't have any cleaning up to do afterwards.

It's been a good day.

Matt Palmer: My entry in the "Least Used Software EVAH" competition

Wed, 2014-10-15 18:26

For some reason, I seem to end up writing software for very esoteric use-cases. Today, though, I think I’ve outdone myself: I sat down and wrote a Ruby library to get and set process resource limits – those things that nobody ever thinks about except when they run out of file descriptors.

I didn’t even have a direct need for it. Recently I was grovelling through the EventMachine codebase, looking at the filehandle limit code, and noticed that the pure-ruby implementation didn’t manipulate filehandle limits. I considered adding it, then realised that there wasn’t a library available to do it. Since I haven’t berked around with FFI for a while, I decided to write rlimit. Now to find the time to write that patch for EventMachine…

Since I doubt there are many people who have a burning need to manipulate rlimits in Ruby, this gem will no doubt sit quiet and undisturbed in the dark, dusty corners of rubygems.org. However, for the three people on earth who find this useful: you’re welcome.

Andrew Pollock: [life] Day 258: Kindergarten, demonstrations and play dates

Tue, 2014-10-14 22:26

I had my second Thermomix demonstration this morning. It was a decent drive from home away, and in my thoroughness to be properly prepared, I somehow managed to misjudge the time and arrived an hour earlier than I needed to. Oops.

It was good to have the additional time up my sleeves though, and I was happy with how the demonstration went, and it left me with a comfortable amount of time to get to Kindergarten to pick Zoe up. It did completely wipe out the day though.

Zoe wanted to watch Megan's tennis class, so I left her with Jason while I popped home to get changed, and then came back in time for the conclusion of tennis class.

Zoe wanted Megan to come over for a play date, so I took Megan back to our place, and the girls had a great afternoon on the balcony doing some self-directed craft. I used the time to play catch up and make a bunch of phone calls.

It wasn't until after Sarah picked up Zoe that I realised I'd barely interacted with her all afternoon though, which was a bit of a shame. I'll be happy once this sausage sizzle on Saturday is done, and the pace of life should slow down a bit more again.

It was a bit of a struggle to force myself to go to yoga class tonight, but I'm glad I did, because it was a really great class.

Andrew Pollock: [life] Day 257: Kindergarten, meetings, and scrounging for sausages

Tue, 2014-10-14 22:26

Zoe's Kindergarten has scored the fundraising sausage sizzle rights to the local Councillor's next Movies in the Park event. Since I've been the chairperson of the PAG, which doesn't seem to actually involve much other than being cheerleader in chief and chairing monthly meetings, I thought I'd lend the fundraising committee a hand with the organising of this event. The fundraising committee have worked their butts off this year.

After I dropped Zoe at Kindergarten, I want to the home of one of the committee members and met with the committee to discuss logistics for the upcoming sausage sizzle. I'd previously volunteered to try and get a donation of sausages from a local butcher, but hadn't had a chance to do that yet.

After taking a bus into the city and back for a lunch meeting, and picking up Zoe from Kindergarten afterwards, we set out on a tour of all the local supermarkets and butchers, with an official letter in hand from the Kindergarten.

We were unlucky on all fronts, but Zoe did score a free cheerio at one butcher, so she was pretty happy. Driving all over the place ate up most of the afternoon.

Anshu dropped in after work not long after we got home, and then Sarah arrived not long after that to pick up Zoe.

Lev Lafayette: Linux and Windows 8 Dual Boot : A Brief How-To

Tue, 2014-10-14 14:29

As regular readers would know, I make some effort to avoid using closed-source and proprietary software. This includes that popular operating system common on laptops and servers, MS-Windows. However there are a small number of reasons why this O.S. is required, including life-saving medical equipment hardware which, for some unfathomable reason, has been written to only interface with proprietary operating systems. Open source developers?

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Stewart Smith: MariaDB Foundation board

Tue, 2014-10-14 11:26

There seems be a bit of an exodus from the MariaDB Foundation board recently… I’m not sure exactly what to make of it all, but the current members according to https://mariadb.org/en/foundation/ are:

  • Rasmus Johansson (chair)
  • Michael “Monty” Widenius
  • Jeremy Zawodny
  • Sergei Golubchik

With Jeremy Zawodny being the only non-MariaDB Corp member.

Recently, Jeremy Cole asked some people about their membership:

@jeremycole Nope. Resigned months ago.

— Mike Milinkovich (@mmilinkov) October 2, 2014

@jeremycole Hi Jeremy, no, sorry, I resigned a little while back.

— Andrew Katz (@andrewjskatz) October 1, 2014

@jeremycole yes, though I'm having some doubts about its future (for a variety of reasons) :-(

— Jeremy Zawodny (@jzawodn) October 1, 2014

I’m a little worried for the project, the idea of a foundation around it and for people I count as friends who work on MariaDB.

Stewart Smith: MySQL 5.7.5 on POWER – thread priority

Tue, 2014-10-14 11:26

Good news everyone!

MySQL 5.7.5 is out with a bunch more patches for running well on POWER in the tree. I haven’t yet gone and tried it all out, but since I’m me, I look at bugs database and git/bzr history first.

On Intel CPUs, when you’re spinning on a spin lock, you’re meant to execute the PAUSE CPU instruction. This tells the CPU that other execution threads in the same core should be given priority as you are currently not doing anything productive. Without this, you’re likely going to hurt on hyperthreaded CPUs.

In MySQL, there are custom spinlocks in order to do interesting adaptive mutex things to attempt to squeeze the most performance possible out of modern systems.

One of the (not 100% ready, but close) bugs with patches I submitted against MySQL 5.7 was for using the equivalent of the PAUSE instruction for POWER CPUs. On POWER, we’re a bit different, you can actually set priorities of threads (which may matter more, as POWER8 CPUs can be in SMT8 mode – where there are *eight* executing threads per core).

So, the good news is that in MySQL 5.7.5, the magic instructions for setting thread priority are in! This should mean great things for performance on POWER systems with any of the SMT modes enabled.

The next interesting part of this is how it interacts with other KVM guests on a system. At least on POWER (and on x86 as well, although I won’t go into details here) there’s a hypervisor call that a guest can make saying “hey, I’m spinning here, perhaps you want to make sure other vcpus execute so that at some point I can continue”. On POWER, this is the H_CONFER hcall, where you can basically do a directed yield to another vcpu (the one that holds the lock you’re trying to get is a good idea).

Generally though, it’s only the guest kernel that does this, not userspace. You can see the H_CONFER call in __spin_yield(arch_spinlock_t*) and __rw_yield(arch_rwlock_t*) in arch/powerpc/lib/locks.c in the kernel.

It would be interesting to see what extra we could get out of a system running multiple guests with MySQL servers if InnoDB/MySQL could properly yield to the right vcpu (well, thread I guess).

Michael Still: One week of Nova Kilo specifications

Mon, 2014-10-13 22:27
Its been one week of specifications for Nova in Kilo. What are we seeing proposed so far? Here's a summary...



API







Administrative



  • Enable the nova metadata cache to be a shared resource to improve the hit rate: review 126705.




Containers Service







Hypervisor: FreeBSD



  • Implement support for FreeBSD networking in nova-network: review 127827.




Hypervisor: Hyper-V



  • Allow volumes to be stored on SMB shares instead of just iSCSI: review 102190.




Hypervisor: VMWare



  • Add ephemeral disk support to the VMware driver: review 126527 (spec approved).
  • Add support for the HTML5 console: review 127283.
  • Allow Nova to access a VMWare image store over NFS: review 126866.
  • Enable administrators and tenants to take advantage of backend storage policies: review 126547 (spec approved).
  • Support the OVA image format: review 127054.




Hypervisor: libvirt



  • Add a new linuxbridge VIF type, macvtap: review 117465.
  • Add support for SMBFS as a image storage backend: review 103203.
  • Convert to using built in libvirt disk copy mechanisms for cold migrations on non-shared storage: review 126979.
  • Support libvirt storage pools: review 126978.
  • Support quiesce filesystems during snapshot: review 126966.




Instance features



  • Allow direct access to LVM volumes if supported by Cinder: review 127318.




Interal



  • Move flavor data out of the system_metdata table in the SQL database: review 126620.




Internationalization







Scheduler



  • Add an IOPS weigher: review 127123 (spec approved).
  • Allow limiting the flavors that can be scheduled on certain host aggregates: review 122530.
  • Create an object model to represent a request to boot an instance: review 127610.
  • Decouple services and compute nodes in the SQL database: review 126895.
  • Implement resource objects in the resource tracker: review 127609.
  • Move select_destinations() to using a request object: review 127612.




Scheduling



  • Add instance count on the hypervisor as a weight: review 127871.




Security



  • Provide a reference implementation for console proxies that uses TLS: review 126958.
  • Strongly validate the tenant and user for quota consuming requests with keystone: review 92507.




Tags for this post: openstack kilo blueprints spec

Related posts: Compute Kilo specs are open; Specs for Kilo; Blueprints to land in Nova during Juno; On layers; My candidacy for Kilo Compute PTL; Juno nova mid-cycle meetup summary: nova-network to Neutron migration



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Linux Users of Victoria (LUV) Announce: LUV Beginners October Meeting: Command Line

Mon, 2014-10-13 12:29
Start: Oct 18 2014 12:30 End: Oct 18 2014 16:30 Start: Oct 18 2014 12:30 End: Oct 18 2014 16:30 Location: 

RMIT Building 91, 110 Victoria Street, Carlton South

Link:  http://luv.asn.au/meetings/map

Wen Lin will be introducing newcomers to Linux to the use of the "command line".

Wen Lin is the long-serving treasurer for Linux Users of Victoria and has provided several presentations in the past on Libre/OpenOffice.

LUV would like to acknowledge Red Hat for their help in obtaining the Buzzard Lecture Theatre venue and VPAC for hosting, and BENK Open Systems for their financial support of the Beginners Workshops

Linux Users of Victoria Inc., is an incorporated association, registration number A0040056C.

October 18, 2014 - 12:30

Michael Still: Compute Kilo specs are open

Mon, 2014-10-13 11:28
From my email last week on the topic: I am pleased to announce that the specs process for nova in kilo is now open. There are some tweaks to the previous process, so please read this entire email before uploading your spec! Blueprints approved in Juno =========================== For specs approved in Juno, there is a fast track approval process for Kilo. The steps to get your spec re-approved are: - Copy your spec from the specs/juno/approved directory to the specs/kilo/approved directory. Note that if we declared your spec to be a "partial" implementation in Juno, it might be in the implemented directory. This was rare however. - Update the spec to match the new template - Commit, with the "Previously-approved: juno" commit message tag - Upload using git review as normal Reviewers will still do a full review of the spec, we are not offering a rubber stamp of previously approved specs. However, we are requiring only one +2 to merge these previously approved specs, so the process should be a lot faster. A note for core reviewers here -- please include a short note on why you're doing a single +2 approval on the spec so future generations remember why. Trivial blueprints ================== We are not requiring specs for trivial blueprints in Kilo. Instead, create a blueprint in Launchpad at https://blueprints.launchpad.net/nova/+addspec and target the specification to Kilo. New, targeted, unapproved specs will be reviewed in weekly nova meetings. If it is agreed they are indeed trivial in the meeting, they will be approved. Other proposals =============== For other proposals, the process is the same as Juno... Propose a spec review against the specs/kilo/approved directory and we'll review it from there.



After a week I'm seeing something interesting. In Juno the specs process was new, and we saw a pause in the development cycle while people actually wrote down their designs before sending the code. This time around people know what to expect, and there are left over specs from Juno lying around. We're therefore seeing specs approved much faster than in Kilo. This should reduce the effect of the "pipeline flush" that we saw in Juno.



So far we have five approved specs after only a week.



Tags for this post: openstack kilo blueprints spec

Related posts: One week of Nova Kilo specifications; Specs for Kilo; Blueprints to land in Nova during Juno; On layers; My candidacy for Kilo Compute PTL; Juno nova mid-cycle meetup summary: nova-network to Neutron migration



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Sridhar Dhanapalan: Twitter posts: 2014-10-06 to 2014-10-12

Mon, 2014-10-13 01:27

Andrew Pollock: [life] Day 254: TumbleTastics and opportunistic play dates

Sun, 2014-10-12 22:25

The problem with being too busy to blog on the day, is by the time I get around to it, I've forgotten half the details...

I can't remember what we did in the morning before TumbleTastics. I think Sarah dropped Zoe around a bit late because she wasn't going to work.

We popped down to the post office to collect some mail, and then the supermarket. After that, Zoe was a bit tired and grumpy (apparently she'd woken up early) and didn't really want to go to TumbleTastics, but after some morning tea, perked up and reconsidered.

We scootered to TumbleTastics, and discovered that one of the boys from Kindergarten, Lachlan, is in her class. She had another really good class, and I invited Lachie and his Mum and little sister over for lunch afterwards.

Lachie and Zoe had a great time playing together, before and after lunch. I think that was the extend of what happened on Friday that was memorable.

Stewart Smith: Tyan OpenPower

Sat, 2014-10-11 18:26

Good news everyone! Tyan has announced the availability of their first OpenPOWER system! They call this a Customer Reference System, which means it’s an excellent machine to start poking at OpenPower and POWER8 (or deploying applications on).

Because it’s an OpenPower machine, it runs the open source Open Power firmware (all up on github) and will happily run Linux (feel free to port your other operating system kernels). I’ll be writing more on the OpenPower firmware soon as, well, technical details are fun!

Ubuntu 14.10 is listed as recommended as not only have they been building for POWER8 but have spent some time ensuring things work fairly well out-of-the-box (both as a KVM guest and running native on the bare metal). Or, you can always just boot whatever the mainline kernel is at – build for the POWERNV (POWER non-virtualized) platform (be sure to include all the required drivers) and have fun!

Chris Smart: Single emergency mode with systemd

Fri, 2014-10-10 19:29

Just to remind myself.. add systemd.unit=emergency.target to the kernel line, or if that fails, try init=/sbin/sh and remove both quiet and rhgb options.

Afterwards, exit or:

exec /sbin/init

Can also enable debug mode to help investigating problems with systemd.log_level=debug

You can get a console early on in the boot process by enabling debug-shell:

systemctl enable debug-shell.service

BlueHackers: BlueHackers @ Open Source Developers’ Conference 2014

Fri, 2014-10-10 16:47

This year, OSDC’s first afternoon plenary will be a specific BlueHackers related topic: Stress and Anxiety, presented by Neville Starick – an experienced Brisbane based counsellor.

We’ll also have our traditional BlueHackers “BoF” (birds-of-a-feather) session in the evening, usually featuring some general information, as well as the opportunity for safe lightning talks. Some people talk, some people don’t. That’s all fine.

The Open Source Developers’ Conference 2014 is being held at the beautiful Griffith University Gold Coast Campus, 4-7 November. It features a fine program, and if you use this magic link you get a special ticket price, but the regular registration is only around $300 anyhow, $180 for students! This includes all lunches and the conference dinner. Fabulous value.

Andrew Pollock: [life] Day 253: Bike riding practice and swim class

Fri, 2014-10-10 16:25

It's been a while since we've done any bike riding practice, and as the day was a bit cooler and more overcast, I thought we could squeeze in a little bit first thing.

We went to the Minnippi Parklands again, and did a little bit of practise. Zoe actually (really briefly) rode her bike for the first time successfully, which was really exciting. We'll have to have another go next week.

After that, we dropped past the supermarket to get a few things for lunch, and then had lunch.

I've managed to forget what happened after lunch, so it can't have been particularly memorable. I miscalculated when swim class was by 30 minutes, and thought we were in more of a rush than we really were. We biked to the Post Office to mail off my US taxes, but I thought we didn't have time to do all the extra paperwork for the mailing, so I paid for the postage, but took all of the stuff with me to swim class to finish filling out. On the way there, I realised I had an extra 30 minutes up our sleeves, which was nice. It gave Zoe some time to have some fruit before class.

Sarah picked up Zoe from swim class, and I biked home to ditch the bike and meet Anshu at the movie theatre to watch Gone Girl. Hoo boy. Good movie.

Andrew Pollock: [life] Day 252: A poorly executed spontaneous outing to Wet and Wild

Fri, 2014-10-10 16:25

The forecast maximum was supposed to be 32°C, so I rather spontaneously decided to go for our first visit to Wet and Wild for the season.

I whipped up some lunch, and got our swim gear together, and after a quick phone call with my REIQ tutor to discuss some questions I had about the current unit, I grabbed our gear and we headed off.

I thought that because school had gone back this week, that Wet and Wild would be nice and quiet, but boy, did I miscalculate. I think the place was the busiest I've ever seen it, even on a weekend visit. It would appear that a lot of people have decided to just take an extra week off school with the Labour Day public holiday on Monday.

Once we arrived, I discovered that I'd left my hat on my bed at home, so I had to buy a hat from the gift shop while I was queuing up to pay for a locker. Then we went to get changed, and I discovered I'd also left my swimming stuff on my bed as well, so I had to line up again to purchase a pair of board shorts and a rashie. I was pretty annoyed with myself at all the unnecessary added expense, because I'd left in too much of a hurry.

After we'd got ourselves appropriately attired, we had a fantastic day. Zoe's now tall enough for a few of the "big kid" slides, so we went on them together as well. The first one just involved us sitting in a big inflatable tube going down a wide, curving slide, so that was pretty easy. The second one I wasn't sure about, because we had to go separately. I went first, and waited at the bottom to catch her. As I went down, I was a bit worried it was going to be too much for Zoe, but she came down fine, and once she surfaced, her first word was "Again!", so it was all good.

She napped on the way home, so I swung by the Valley to check my post office box, and then we got home and Sarah picked her up. In spite of the extra expense, it was a really good day out.

Lev Lafayette: Free and Open Source Software Business Applications

Thu, 2014-10-09 09:29

Free and open source software is based on key principles that are firmly grounded in instrumental advantages and ethical principles. It is heavily used in infrastructure and in new hardware forms; it is less used in user-end applications and traditional forms (laptops and desktops); however there is a good range of mature and feature-rich business applications available. The development of increasingly ubiquitous and more powerful computing is particularly well-suited for FOSS and workplaces that make use of such software will gain financial and positional advantages.

Presentation to Young Professionals CPA, October 8, 2014

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Michael Still: Lock In

Wed, 2014-10-08 21:28






ISBN: 0765375869

LibraryThing

I know I like Scalzi stuff, but each series is so different that I like them all in different ways. I don't think he's written a murder mystery before, and this book was just as good as Old Man's War, which is a pretty high bar. This book revolves around a murder being investigated by someone who can only interact with the real world via personal androids. Its different from anything else I've seen, and a unique idea is pretty rare these days.



Highly recommended.



Tags for this post: book john_scalzi robot murder mystery

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