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obtu

580 karma · joined November 16, 2011

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obtu··on Storing Date/Times in Databases
The date of the meeting mustn't depend on the display preferences of one of the participants. The meeting itself has to be anchored to a time zone.
obtu··on Storing Date/Times in Databases
You missed one of his requirements, which is he wants be able to compute "three months after" on the dates he stores, which is a timezone-sensitive calculation. This sort of requirement is commonly found in calendaring. That means he does need to store symbolic information for each date or datetime stored.
obtu··on Git-based fabric deploys are awesome

    export PYTHONDONTWRITEBYTECODE=1
may be more convenient than passing -B.
obtu··on Firefox 15 now supports in-content preferences
in-content means the preferences dialog get changed to a tab (à la Chrome). It's not about changing preferences to be per-site (there are some per-site prefs in right-click, view page info, permissions).
obtu··on TCP doesn't suck, and all the proposed bufferbloat fixes are identical
Or you can test negotiation towards a particular host using this patched scamper, a traceroute-like tool: http://test-ecn.csail.mit.edu/
obtu··on South Korea Still Paying The Price For Embracing Internet Explorer A Decade Ago
Native code, that is trusted on the basis of having been signed by a special editor cert which the user has to accept. You may have encountered it if you've ever used windows update. Not sandboxed at all, unlike Java.
obtu··on TCP doesn't suck, and all the proposed bufferbloat fixes are identical
I don't see it in netstat -s.

Possibly you'd have to hack up a netfilter rule.

obtu··on TCP doesn't suck, and all the proposed bufferbloat fixes are identical
There's nothing the XP computer can do to fix that, as it is the victim of the delays and needs the cooperation of other hosts that are to some degree involved in causing the problem. As I understand it, ECN on the Mac enables the Mac to cooperate with queue management elsewhere (the Mac could be doing its own queue management without ECN, but probably doesn't). The Quake trouble indicates the bottleneck is an overlarge buffer on a router you both share. You need your shared router to do some queue management (CeroWrt is a good platform for this) so that large downloads don't increase delays for all connections. If your ISP modem has bloated buffers and you can't replace it, you may be entirely out of luck.
obtu··on TCP doesn't suck, and all the proposed bufferbloat fixes are identical
Continuing this bufferbloat conversation, here is a shameless plug about CoDel: https://news.ycombinator.com/item?id=3948725

It implements the “look at the time you've had a queue above threshold” bit.

obtu··on CoDel: wireless-friendly adaptive queue management
This is a new algorithm to fight bufferbloat by Kathleen Nichols and Van Jacobson. It has no tunables, and is able to adapt to bandwidth changes of two orders on magnitude, making it suitable for radio links (3G, WiFi).

Patches for the CeroWrt home router are being tested: https://gettys.wordpress.com/2012/05/08/fundamental-progress... Via https://lwn.net/Articles/496250/

obtu··on PostgreSQL Magazine #01 is out
2012, read again.
obtu··on TCP doesn't suck, and all the proposed bufferbloat fixes are identical
Huh, I wasn't aware ECN wasn't enabled everywhere yet.

To enable it on Linux:

    sudo sysctl net.ipv4.tcp_ecn=1
Across reboots:

    echo net.ipv4.tcp_ecn=1 |sudo tee /etc/sysctl.d/10-ecn.conf
Other OSes: https://en.wikipedia.org/wiki/Explicit_Congestion_Notificati...
obtu··on Timeline of the far future
Sure. Quite possibly we'll just see refinements at the edges of what we have access to (because at most scales, physics is already very accurate) rather than outright revolutions.
obtu··on Timeline of the far future
We've done things that seem like magic to some hunter-gatherer; that doesn't imply everything that seems like magic to us will come true. (does anyone have a catchy name for this fallacy?)

The boundary between things we know to be possible and impossible is in fact stronger now, because (for most of the events in this timeline) we're now basing this knowledge on the laws of physics.

Sidebar: future events that derive solely from thermodynamics don't really have a get-out-of-jail card; deflecting some of the others would require us to meaningfully harness much larger amounts of energy at the scholar system scale, bootstrapping that sort of thing would require multiple jumps of a few orders of magnitude which might be solvable as an engineering problem, but is economically dicey when we're already squandering the fossil fuel dividend on our current, unsustainable needs. That is to say, please solve politics or economics before dreaming of magitech.

obtu··on 3x faster linux boot with e4rat
Since ureadahead looks at blocks and not files, it has a potential speed advantage if the boot process is opening some large files but not reading them in full.

Edit: except the ureadahead packfile only points to the blocks and files, it does not provide a way to inline them. So e4rat is almost certainly faster. It's a shame it is ext4 specific.

Apparently Scott James Remnant, the ureadahead developer, considered feeding the collected info to a defragmenter: http://ubuntuforums.org/showthread.php?t=1434502 ; this would be nice, as it means a single package is responsible for the feature, and filesystems perform to the best of their ability whether or not they have ext4-like fine-grained control of defragmentation.

obtu··on 3x faster linux boot with e4rat
The OSX feature apparently notices files which are slowly appended to (downloads) and defragments them. It does not reallocate a set of files (such as the ones touched at boot) to be adjacent on disk, which is what e4rat does.
obtu··on 3x faster linux boot with e4rat
I have btrfs (with lzo compression) on a rotating disk, and the boot feels a little slower (one or two minutes total?) for reasons I haven't really examined. I'll have to check if something messed with ureadahead.
obtu··on 3x faster linux boot with e4rat
I wonder how much improvement that brings over standard ureadahead (see yason in this thread for how they differ). For zram, no need for a ppa, a zram-config package has been added in precise.
obtu··on Video Stabilization on YouTube
As I understand it the motion blur is a product of lossy compression (CCD has very short pixel-local exposure times; the shearing the article refers to appears when sweeping the whole image); which means that yes, stabilisation algorithms would work best with source data that hasn't been compressed using a perceptual model of motion blur.
obtu··on A Relevant Tale: How Google Killed Inktomi
To be fair, faster answers + the ability to undo a do-what-I-mean guess lets me correct Google's assumptions pretty fast. The tools at the left allow for some quick refining as well; that's pretty useful when I need particularly fresh results, or a time window from when some news was breaking. And the fast completion is useful to refine a query before it returns results (though occasionally annoying when it erases quotes and the like).
obtu··on Python Application Deployment with Native Packages
I'm a bit wary of calling an fpm-generated deb a native package, those are about as well integrated as a checkinstall (make install -> deb) or an alien (rpm -> deb) package. fpm may still be useful for this use case, but it doesn't take me much more effort to get a proper source package.
obtu··on Want good programmers? Then pay them.
I see some ambiguity: this is the contract negociation; the work may be referring to the entire duration of his employment. Exceptional circumstances are exceptional, and he may choose to give up his Friday then.
obtu··on I'm Giving Up Reading for a Year
http://youtu.be/EC0TDci9hqg — as mocked by Mitchell & Webb (That Mitchell & Webb Look series 2)
obtu··on Weebly CEO David Rusenko: It’s Time to Take Us Seriously
By that metric MySpace hosts about 100% of all websites, and YouTube hosts 100 000% of all TV channels.
obtu··on What every programmer should know about memory, Part 1
He mentioned the data structure is large, so it's a safe assumption to say the cpu caches won't be useful except maybe for the very top of the tree, and that there is no locality when traversing a tree path.
obtu··on Peak plastic
Distributed thinking isn't rational even if the actors are, it all depends on the rules of the game. For example, the optimal strategy in a prisonner's dilemma hurts both players; tragedies of the commons have similar effects at a larger scale. There is no objective standard saying how much future discounting is rational, although obviously I'd prefer one that doesn't discount significantly until after one or two lifetimes.

Burning the stuff now is a perfect example of future discounting: it values having energy now over having something that can be used and reused. It's also an example of tragedy of the commons: the energy utility goes to whoever uses it, climate change is a cost for everyone, and unregulated markets don't minimise those costs.

obtu··on Peak plastic
Using petrol on personal transportation is such a waste. I'd like to see a heavy carbon tax so that this fantastic, but finite, resource would be directed to things where it really adds value. The US subsidising wars to get more of it makes selfish sense, but to burn it immediately instead of building infrastructure is shameful.
obtu··on Building Robust Systems - Gerald Sussman (2007) [pdf]
This is a biological metaphor that has been stretched too far. Natural selection has produced impressive systems and ecosystems that provide some redundancy, but humans are much better at deliberate effort and fast conscious feedback loops, and as long as humans are writing software the way we do it should play to human strengths.
obtu··on Introducing the New GitHub Graphs
Weekday and hour of commit times (relative to the commiter's timezone; I remember the previous version used some GitHub timezone). Not sure if they use CommitTime or AuthorTime.
obtu··on Worldwide Mirrors of git.kernel.org
Other subdomains:

https://chromium.googlesource.com/

https://android.googlesource.com/

https://android-review.googlesource.com/

https://gerrit.googlesource.com/

https://gerrit-review.googlesource.com/

https://*-review.googlesource.com/

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