Made by Mikal – Page 43

Wow, qemu-img is fast

Post author:mikal
Post published:February 4, 2012
Post category:OpenStack

I wanted to determine if its worth putting ephemeral images into the libvirt cache at all. How expensive are these images to create? They don't need to come from the image service, so it can't be too bad, right? It turns out that qemu-img is very very fast at creating these images, based on the very small data set of my laptop with an ext4 file system... mikal@x220:/data/temp$ time qemu-img create -f raw disk 10g Formatting 'disk', fmt=raw size=10737418240 real 0m0.315s user 0m0.000s sys 0m0.004s mikal@x220:/data/temp$ time qemu-img create -f raw disk 100g Formatting 'disk', fmt=raw size=107374182400 real 0m0.004s user 0m0.000s sys 0m0.000s Perhaps this is because I am using ext4, which does funky extents things when allocating blocks. However, the only ext3 file system I could find at my place is my off site backup disks, which are USB3 attached instead of the SATA2 that my laptop uses. Here's the number from there: $ time qemu-img create -f raw disk 100g Formatting 'disk', fmt=raw size=107374182400 real 0m0.055s user 0m0.000s sys 0m0.004s So still very very fast. Perhaps its the mkfs that's slow? Here's a run of creating a ext4 file system inside that 100gb file I just made on…

Slow git review uploads?

Post author:mikal
Post published:February 3, 2012
Post category:OpenStack

jeblair was kind enough to help me debug my problem with slow "git review" uploads for Openstack projects just now. It turns out that part of my standard configuration for ssh is to enable ControlMaster and ControlPersist. I mostly do this because the machines I use at Canonical are a very long way away from my home in Australia, and its nice to have slightly faster connections when you ssh to a machine. However, gerrit is incompatible with these options as best as we can tell. So, if your git reviews are taking 10 to 20 minutes to upload like mine were, check that you're not using persistent connections. Excluding review.openstack.org from that part of my configuration has made a massive difference to the speed of uploads for me.

Announcement video

Post author:mikal
Post published:February 1, 2012
Post category:Conference

I imagine that most people saw this at the conference closing. However, for completeness and because I feel that if we're going to put videos of other speakers online then I should suffer the same fate, here is the LCA 2013 announcement from Ballarat:

Shadow of a Dark Queen

Post author:mikal
Post published:January 27, 2012
Post category:Book

I read this book before LCA 2012, but never had a chance to mention it here. It was the first return to Midkemia for me since I read the Krondor's Sons books. This book is set a lot later, and there is very little reuse of characters between The Riftwar Saga or even Krondor's Sons. The only real overlap is the presence of Pug briefly. This book over does its "dirty dozen" aspects, with much of the book focusing on the military training of criminals. The rest of the book feels like a rushed military adventure in a far land, and could have done with some more attention. However, the book isn't terrible, and I thought it was ok overall. [isbn: 9780006480266;0006480268]

Are you in a LUG? Do you want some promotional materials for LCA 2013?

Post author:mikal
Post published:January 26, 2012
Post category:Conference

Canberra was announced as the host for LCA 2013 at the close of LCA 2012. As part of that closing, we handed out postcards and laptop stickers to delegates. However, we deliberately had extra printed on the theory that groups like LUGs, university computer societies and so forth would be interested in having promotional materials for their groups. For those of you not lucky enough to attend the excellent LCA2012, the stickers looked like this: And the postcards look like this: All credit for the excellent art should go to the very capable Jenny Cox. So, if you're interested in having some stuff to hand out at your next LUG or computer society meeting, please drop us a line at contact@lca2013.linux.org.au. Don't forget to include the name of the group and a mailing address.

linux.conf.au Returns to Canberra in 2013

Post author:mikal
Post published:January 22, 2012
Post category:Conference

I am incredibly pleased to announce that linux.conf.au 2013 will be hosted by Canberra, Australia between 28 January 2013 to 2 February 2013. As the director for 2013 I have been blessed with a simply incredible team who has done fantastic work during the bid process, and I am confident that we will pull off a fantastic event. 2013 is Canberra's centenary year, so I think its appropriate to have a conference with a bit of a party atmosphere. We're working hard already on making 2013 a conference to remember. For those who were unable to see the announcement at the conference, you might find the following interesting: Call for papers: June 2012 Early bird registrations open: October 2012 Conference: 28 January 2013 to 2 February 2013 linux.conf.au is one of the foremost open source conferences in the world, and is considered the most prestigious in the southern hemisphere. Many of the team that brought you linux.conf.au 2005 are coming back to help with the 2013 effort, and we're cognizant of the extremely high standard left by previous conferences, especially the astounding job that Josh's 2012 team did. The web site for the conference http://lca2013.linux.org.au is already live, and we'll…

Its a good sign that they’re already making fun of me, right?

Post author:mikal
Post published:January 4, 2012
Post category:Conference

So, today on IRC... 16:07 <mikal> So, breakfast catering at the student accommodation... Will there be bacon? 16:07 <ctudball> mikal: You have my permission to riot if there is no bacon. 16:07 <mikal> Yay! 16:07 <mikal> Real coffee? 16:08 <ctudball> mikal: No. 16:08 <mikal> ! ... 16:10 <mikal> I can still add breakfast to my rego, right? 16:10 <mikal> I'll just fill a sock with $18 worth of bacon each morning 16:11 <ctudball> mikal: You can! 16:11 <mikal> Ok, that's official authorization for Operation Bacon Sock ... 16:11 <mikal> If anyone complains, I am showing them a lightly edited version of this IRC log Which somehow became baconsock.org.

Further adventures with base images in OpenStack

Post author:mikal
Post published:January 4, 2012
Post category:OpenStack

I was bored over the New Years weekend, so I figured I'd have a go at implementing image cache management as discussed previously. I actually have an implementation of about 75% of that blueprint now, but its not ready for prime time yet. The point of this post is more to document some stuff I learnt about VM startup along the way so I don't forget it later. So, you want to start a VM on a compute node. Once the scheduler has selected a node to run the VM on, the next step is the compute instance on that machine starting the VM up. First the specified disk image is fetched from your image service (in my case glance), and placed in a temporary location on disk. If the image is already a raw image, it is then renamed to the correct name in the instances/_base directory. If it isn't a raw image then it is converted to raw format, and that converted file is put in the right place. Optionally, the image can be extended to a specified size as part of this process. Then, depending on if you have copy on write (COW) images turned on or…

The Ghost Brigades (2)

Post author:mikal
Post published:December 30, 2011
Post category:Book

The second time around I think my opinion has changed a little. I found the plot a little hard to believe (perhaps I am scarred by other book's twee explorations of the motivations of alien species), and overall the book not as good as Old Man's War. Then again, its far from the worst book I have read this year. Original post about this book. [award: nominee prometheus 2007] [isbn: 0765354063]

Red Mars

Post author:mikal
Post published:December 21, 2011
Post category:Book

This is another book on colonization. To be totally honest I enjoyed the first half of the book more than the second, and I rather thought the book dragged on and could have done with a more vigorous editing. There are sections which are deeply descriptive, but it doesn't progress the story. Overall, I was a little disappointed.