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bos on Facebook hit git performance issue on large repository - http://www.reddit.com/r...
"Reposting what I wrote over on [Hacker News](http://news.ycombinator.com/item...), where this story originated: Facebook engineer here, working on this problem with Joshua. What this comes down to is that git uses a lot of essentially O(*n*) data structures, and when *n* gets big, that can be painful. A few examples: * There's no secondary index from file or path name to commit hash. This is what slows down operations like `git blame`: they have to search every commit to see if it touched a file. * Since git uses `lstat` to see if files have been changed, the sheer number of system calls on a large filesystem becomes an issue. If the dentry and inode caches aren't warm, you spend a ton of time waiting on disk I/O. An inotify daemon could help, but it's not perfect: it needs a long time to warm up in the case of a reboot or crash. Also, inotify is an incredibly tricky interface to use efficiently and reliably. (I wrote the inotify support in Mercurial, FWIW.) * The index is..." - Bryan O'Sullivan
reddit is offline in protest of PROTECT IP and SOPA - http://www.reddit.com/
"submitted by reddit to blog." - Bryan O'Sullivan
bos on Conduits, part 5 (of 5): Buffering - http://www.reddit.com/r...
"> This makes certain kinds of usage incredibly. You accidentally the." - Bryan O'Sullivan
7800 Bar & Grill (4/5) - http://www.yelp.com/biz...
Map
"New place open where the old Tower Bar was. It's fairly small and cosy, with a decent bar and menu, and prices that you'll definitely like if you're used to typical ski resort gouging. I especially…" - Bryan O'Sullivan
bos on Conduits, part 2 of ?: five minute guide, and sources in depth - http://www.reddit.com/r...
"I'm really lookin forward to seeing where the conduit work goes. Very much liking the first few posts in this series. Even the terminology is muh easier to follow than the enumerator business." - Bryan O'Sullivan
bos on criterion 0.6 produces shiny new performance reports - http://www.reddit.com/r...
"Er, no? Firstly, the flot plotting library doesn't support axis labels (I know, right?). But I managed to fudge a way to get units on the x axis; whew! But the y axis has very little meaning on both charts, so it doesn't make sense for it to be labeled. The heights I spikes in the KDE chart are visually useful, but they do *not* correspond to probabilities or any other number you could do anything with." - Bryan O'Sullivan
The Last Colony (Old Man's War, #3) - http://www.goodreads.com/review...
The Ghost Brigades (Old Man's War, #2) - http://www.goodreads.com/review...
The future of MailRank’s open source technologies - http://www.serpentine.com/blog...
A major new release of the Haskell statistics library - http://www.serpentine.com/blog...
Salomon Freeski TV S5 E05 The Freedom Chair - http://www.youtube.com/watch...
Salomon Freeski TV S5 E05 The Freedom Chair
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Pushing Boundaries - Featuring Henrik Windstedt - Film 4 - http://www.youtube.com/watch...
Pushing Boundaries - Featuring Henrik Windstedt - Film 4
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bos on [Newbie]: Haskell code is really slow compared to same code in Python. Can anyone help me find what the problem is ? - http://www.reddit.com/r...
"Independent of the bugs in your code, I think that the radix-2 DIT FFT (which is what this is) is one of those algorithms where the in-place version is both way more efficient and easier to follow. So you can see what I mean, here's an implementation of that algorithm that I wrote a few weeks ago: https://github.com/bos..." - Bryan O'Sullivan
Pabst Blue Ribbon commercial - 1979 - starring Patrick Swayze - http://www.youtube.com/watch...
Pabst Blue Ribbon commercial - 1979 - starring Patrick Swayze
Play
bos on Haskell and binary streams: parsing with field interdependencies - http://www.reddit.com/r...
"I'd be curious too, since I wrote attoparsec." - Bryan O'Sullivan
HEAD Skiers United - Episode One - http://www.youtube.com/watch...
HEAD Skiers United - Episode One
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Salomon Freeski TV S5 E03 This is Norway - http://www.youtube.com/watch...
Salomon Freeski TV S5 E03 This is Norway
Play
Salomon Freeski TV S5 E03 This is Norway - http://www.youtube.com/watch...
Salomon Freeski TV S5 E03 This is Norway
Play
Retallack - The Movie [ Tanner Hall ] - http://www.youtube.com/watch...
Retallack - The Movie [ Tanner Hall ]
Play
The Adventurer - Featuring Dave Treadway - Film 3 - http://www.youtube.com/watch...
The Adventurer - Featuring Dave Treadway - Film 3
Play
The Adventurer - Featuring Dave Treadway - Film 3 - http://www.youtube.com/watch...
The Adventurer - Featuring Dave Treadway - Film 3
Play
Kayaking with Redondo Beach Blue Whales, with underwater footage and Lunge feeding GoPro - http://www.youtube.com/watch...
Kayaking with Redondo Beach Blue Whales, with underwater footage and Lunge feeding GoPro
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M83 'Midnight City' Official video - http://www.youtube.com/watch...
M83 'Midnight City' Official video
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Fast optimal bandwidth estimation for univariate KDE - http://www.umiacs.umd.edu/labs...
Efficient use of Kernel density estimation (KDE) requires the optimal selection of the smoothing parameter called the bandwidth h of the kernel. For a practical implementation of KDE the choice of the bandwidth h is very important. Small h leads to an estimator with small bias and large variance. Large h leads to a small variance at the expense of increase in bias. The bandwidth h has to be chosen optimally. The most successful among all the current methods, both empirically and theoretically, is the solve-the-equation plug-in method. However this is computationally very expensive and scales as O(N^2). The code given here computes the same in O(N) time at the expense of reduced precision, which can be arbitrary. - Bryan O'Sullivan
Kernel Density Estimator - File Exchange - MATLAB Central - http://www.mathworks.com/matlabc...
Reliable and extremely fast kernel density estimator for one-dimensional data. Gaussian kernel is assumed and the bandwidth is chosen automatically. Unlike many other implementations, this one is immune to problems caused by multimodal densities with widely separated modes. - Bryan O'Sullivan
Salomon Freeski TV S5 E01 La Niña - http://www.youtube.com/watch...
Salomon Freeski TV S5 E01 La Niña
Play
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