Because opec is saying peak oil is near.

happy solstice!

December 22, 2006

Here’s to progressively more daylight!

Yum optimizations

December 21, 2006

I got play with a shell on an OLPC box last week thanks to Chris Blizzard and it had the advantage of being so slow and low on memory that it really shows off where yum performs for crap. I’ve been spoiled by fast hardware b/c of my job so I’ve not seen some of these issues at all. However, I’ve seen them now and we’re looking at some creative solutions.

The first one and somewhat controversial is possibly doing away with the xml->sqlite conversion on the client side. Essentially, on each run of yum it checks for new metadata, downloads the xml files, and imports them. Now, in yum 3.0 Tambet Ingo introduced a c-based python module that would do the xml->sqlite conversion very quick. However, even with the module the OLPC box took 4-6 minutes to import the metadata of fedora core and extras. That’s a world of suck. So, I started to compare sizes of the compressed sqlite files and the compressed xml files, and checking to make sure that sqlite would play nice if moved from various architectures to others. All those things seem to be correct. So, what we’re thinking of doing is dropping a premade sqlite db into each repository as another optional metadata piece. Then yum clients which understood to look for them could download them and be able to skip the metadata conversion step entirely. On fast systems that’s really only saving 7-15 seconds. On slow systems it saves many minutes.

The next thing we’ll be doing is going through the db format on disk and seeing if we missed any format benefits that could make searching faster. (which makes depsolving faster). Additionally, Panu pointed out the advantage of certain indexes on performance.

Finally, I think we’ll be rifling through the depsolving routines to look for obvious caching opportunities in the routines.

I’d like to ask folks who are interested in profiling or optimizing yum w/o fundamentally altering its behavior to take a look through this thread and if you have something to add, please do so.

puzzle board

December 20, 2006

puzzle board

Originally uploaded by skvidal.

This is the top secret project I’ve been working on for Christmas/Solstice/etc. It’s a board for us to work on jigsaw puzzles on. It’s just a 1/2in thick 38″ square piece of plywood that’s been sanded and poly-urethaned for a few coats. I attached two yardsticks for alignment and to give it an edge for the puzzle to rest against. This will help us as our puzzles are getting bigger than our conveniently available table space.

It took a little while to get it all set but it makes me happy b/c it is something kinda neat and it is outside of the set of things I normally work on.


December 15, 2006

I was in germany a week ago. Berlin, in fact. There’s this vocalist named Vienna Teng who I have wanted to see in concert for a while and kept being out of town whenever she was going to be nearby. So I’m in Berlin Dec 3rd -> Dec 7th. She’s performing in Berlin Dec 6th and I didn’t know and didn’t go.

It’s astounding.

borrowed books

December 10, 2006

If anyone reading this borrowed any ray bradbury books from me – specifically ‘the vintage bradbury’ please email me.

I’m going mildly bonkers trying to figure out where it went.



December 9, 2006

two excerpts about October:

“And if it’s around October twentieth and everything smoky-smelling and the sky orange and ash gray at twilight, it seems Halloween will never come in a fall of broomsticks and a soft flap of bedsheets around corners.”

– Something Wicked This Way Comes – Ray Bradbury

“October was in the chair, so it was chilly that evening, and the leaves were red and orange and tumbled from the trees that circled the grove. The twelve of them sat around a campfire roasting huge sausages on sticks, which spat and crackled as the fat dripped onto the burning applewood, and drinking fresh apple cider, tangy and tart in their mouths.”

– October in the Chair – Neil Gaiman doing his very best Ray Bradbury impersonation.

Both of the above are from two books I read this last week. Such lovely descriptions of October and they contain, for the most part, my overwhelming thoughts and impressions of October when I was little.